JP4971784B2 - Ink media set, ink cartridge, ink jet recording method, ink jet recording apparatus, and ink recorded matter - Google Patents

Description

  The present invention relates to an ink media set capable of obtaining a high-quality image with high chroma and good color tone even on a recording medium having low ink absorbability, and an ink jet recording method and an ink jet recording apparatus using the ink media set. And an ink recorded matter.

  Inkjet printers are remarkably popular because of their low noise and low running costs, and color printers that can print on plain paper are also being actively put on the market. However, image color reproducibility, rub resistance, light resistance, gas resistance, water resistance, image drying, character bleeding (feathering), color boundary bleeding (color bleed), solid density unevenness (beading) ), It is very difficult to satisfy all required characteristics such as double-sided printing property and ejection stability, and an ink composition and a recording medium to be used are selected from characteristics preferentially according to the use.

Ink compositions used for inkjet recording generally contain water as a main component and contain a colorant and a wetting agent such as glycerin for the purpose of preventing clogging. As the colorant, a water-soluble dye capable of obtaining a vivid color is mainly used.
However, there is a problem that dyes have poor light resistance, gas resistance, and water resistance and do not reach acceptable quality on plain paper. In order to solve this problem, although attempts have been made to improve the durability by improving the ink jet recording paper having an ink absorbing layer, there is a problem that sufficient quality is not achieved.

Therefore, pigments have been used in recent years because they have excellent light resistance, gas resistance and water resistance as colorants. However, the color developability is inferior to that of dyes. This is considered to be caused by interference of light of different wavelengths and phases due to multiple reflection of light inside the pigment.
Therefore, when a pigment is used as the colorant of the ink composition for ink jet recording, there are problems such as a decrease in saturation on plain paper and a decrease in gloss on recording paper dedicated for ink jet recording. In order to solve these problems, attempts have been made to improve the saturation by making the pigment particles finer, and attempts have been made to improve the glossiness by coating the pigment particles with a polymer, but there is still a difference in color development from the dyes. To do.

In addition, as a recording medium used for ink jet recording, for example, a medium having high water absorbability such as plain paper or ink jet recording paper is used, and generally measured by a dynamic scanning absorption meter. The amount of pure water transferred to the recording medium at a contact time of 100 ms exceeds 35 ml / m ² , and the amount of pure water transferred to the recording medium at a contact time of 400 ms exceeds 40 ml / m ² . Value.
Thus, plain paper with good absorbency has the advantage of being thin and inexpensive. There is a problem that the image of the sunken impression. Moreover, since the recording paper for exclusive use of the ink jet provides recording properties by providing a layer of an inorganic pigment or a water-absorbing polymer on the surface, a coloring component can be left in the vicinity of the surface and high color development can be obtained. However, there is a problem that the paper becomes thicker and becomes more expensive than the plain paper.

Examples of the recording medium include a polymer film having no receiving layer on the surface. These are measured by a dynamic scanning absorptiometer, and the transfer amount of pure water to the recording medium at a contact time of 100 ms is less than 2 ml / m ² , and the pure water to the recording medium at a contact time of 400 ms is used. Is less than 3 ml / m ² .
Since such a recording medium hardly absorbs water, problems such as offset dirt and white spots (hereinafter sometimes referred to as “spur dirt”) due to spurs, beading, and back dirt during stacking frequently occur. It is not something that can withstand practical use.

Moreover, surface-coated paper etc. are mentioned as a recording medium. These are measured by a dynamic scanning absorption meter, and the amount of pure water transferred to the recording medium at a contact time of 100 ms is ² to 35 ml / m ² , and the recording medium of pure water at a contact time of 400 ms is used. The transfer amount to 3 to 40 ml / m ² . Such a recording medium is mainly used for applications such as offset printing and gravure printing, and is thin in thickness and is not much different from plain paper. When printing on such a recording medium using water-based inkjet ink, when the colorant is a pigment, the coloring material stays on the surface, so that a high-quality image with excellent color development and high gloss can be obtained. Can do. However, when the colorant is an aqueous dye, the colorant does not stay on the surface and moves to the substrate (cellulose) side through the holes in the surface coat layer together with moisture and water-soluble solvent, so it is dull at a low concentration. There is a problem of color development.
Further, when a pigment ink is used, a high color image can be obtained. However, since the ink composition is dried slowly, there is a problem that spur dirt, beading, back dirt at the time of stacking or the like occurs.

Several methods have been proposed to solve the drying of the ink composition. For example, a method using strongly alkaline ink has been proposed (see Patent Document 1). However, in this proposal, there is a problem in handling, and there is a problem that the fixing property tends to be significantly lowered with neutral paper.
There has also been proposed a method for recording using an oil-based ink composition using a water-insoluble organic solvent as a liquid medium. However, this proposal has excellent fixability, but it needs to be considered for the odor and safety of organic solvents, so it is only used for industrial purposes. There is a problem that it is not.
In addition, methods using an ink composition containing a large amount of a surfactant, an ink composition using a surfactant having a low surface tension, and the like have been proposed (see Patent Document 2). However, in this proposal, although the drying speed of the ink composition after printing is superior to that of the conventional ink composition, depending on the paper, if the printed matter coming from the recording device is picked up immediately, There is a problem that the composition may be stained, and depending on the paper, the feathering becomes remarkable.
In addition, a method has been proposed in which recording is performed by heating a solid wax-like ink composition at normal temperature and discharging it in a molten state (see Patent Document 3). However, in this proposal, there is a problem that the printed portion is raised and the printed matter may be transferred if a plurality of printed materials are left to stand, and the papers are stuck together. Another problem is that the device becomes complicated because a means for heating the ink composition is required.
In addition, a method for promoting drying by heating the recording paper after printing has been proposed (see Patent Document 4). However, this proposal requires a device such as a heating roller and a hot air generator, which causes a problem that power consumption is increased and cannot be used in an office or a general household.

As described above, the colorant using the dye is superior in color developability as compared with the colorant using the pigment, but as described above, the light resistance, gas resistance, and water resistance are poor. There is a problem that the paper does not reach an acceptable quality.
In order to solve this water resistance, gas resistance, and light resistance, a method using a coloring material in which a dye is dissolved or included in polymer fine particles has been proposed (see Patent Documents 5 to 8). In these proposals, water-insoluble dyes are mainly used, and it becomes possible to obtain water resistance and gas resistance equivalent to those of pigments while maintaining high color developability of the dyes. However, these proposals are limited to recording on plain paper or inkjet recording paper, and recording media with low absorbency (specifically, pure water with a contact time of 100 ms is recorded on the recording media). When the transfer amount is less than 4 ml / m ² and the transfer amount of pure water to the recording medium at a contact time of 400 ms is less than 5 ml / m ² ), the occurrence of beading and drying properties are reduced. There is a problem of becoming insufficient.

  Further, in order to solve the problem of drying caused when the colorant using the dye is used for a recording medium having low absorbency, the viscosity of the aqueous ink composition containing the dye in a polymer emulsion is increased. A method has been proposed (see Patent Document 9). However, in this proposal, the higher the viscosity, the higher the solid content in the ink composition and the faster the drying, so it is effective for recording paper with high absorbency, but used for recording media with low absorption. There is a problem that in some cases it is insufficient.

  Therefore, it is desired to develop an ink media set capable of obtaining a high-quality image with high color saturation not only on plain paper and inkjet recording paper but also on a recording medium with low ink absorbability. Is the current situation.

Japanese Patent Laid-Open No. 63-2996 JP 60-34992 A JP-A-2-18710 JP 2003-72059 A JP 7-268260 A Japanese Patent Laid-Open No. 10-245511 Japanese Patent Laid-Open No. 10-251567 Japanese Patent No. 2977717 JP 2005-306899 A

  This invention is made | formed in view of this present condition, and makes it a subject to solve the said various problems in the past and to achieve the following objectives. That is, the present invention relates to an ink media set that has high saturation and a high-quality image with good color tone not only on plain paper and inkjet recording paper but also on recording media with low ink absorption, and the ink media set. It is an object of the present invention to provide an ink cartridge, an ink jet recording method, an ink jet recording apparatus, and an ink recorded matter using the above.

  As a result of intensive studies by the present inventors in order to solve the above problems, the following knowledge has been obtained. That is, by using a combination of a specific ink composition and a specific recording medium, not only plain paper and inkjet recording paper but also recording media with low ink absorption have high saturation and good color tone. This is a knowledge that a high-quality image can be obtained.

This invention is based on the said knowledge by the present inventors, and the means for solving the said subject are as follows. That is,
<1> An ink media set having an ink composition and a recording medium,
The ink composition contains polymer fine particles including dyes and inorganic pigment particles, a water-soluble solvent, and water, and has a surface tension at 25 ° C. of 20 to 35 mN / m,
The recording medium comprises a support and a coating layer on at least one surface of the support, and pure water is applied to the recording medium at a contact time of 100 ms measured with a dynamic scanning absorptiometer. The transfer amount is 2 ml / m ² or more and less than 35 ml / m ² , and the transfer amount of pure water to the recording medium at a contact time of 400 ms is 3 ml / m ² or more and less than 40 ml / m ^2. Ink media set.
<2> The ink media set according to <1>, wherein the ink composition has a viscosity at 25 ° C. of 5 to 50 mPa · s.
<3> The ink media set according to any one of <1> to <2>, wherein the dye is at least one of an oil-soluble dye and a disperse dye.
<4> The ink media set according to any one of <1> to <3>, wherein the inorganic pigment particles are any of titanium dioxide particles, alumina particles, and silica particles.
<5> The above <1> to <4>, wherein the polymer constituting the polymer fine particles including the dye and the inorganic pigment fine particles is at least one of a polyester resin, a polyurethane resin, a vinyl resin, and an acrylic resin. The ink media set according to any one of the above.
<6> The ink media set according to any one of <1> to <5>, wherein the polymer fine particles including the dye and the inorganic pigment fine particles have a volume average particle diameter of 5 to 200 nm.
<7> The water-soluble solvent is glycerin, diethylene glycol, triethylene glycol, 1,3-butanediol, 1,6-hexanediol, propylene glycol, 1,5-pentanediol, dipropylene glycol, trimethylolpropane, and 3 -The ink media set according to any one of <1> to <6>, which is at least one of methyl-1,3-butanediol.
<8> The ink media set according to any one of <1> to <7>, including any one of a polyol compound having 8 or more carbon atoms and a glycol ether compound.
<9> An ink cartridge comprising the ink composition of the ink media set according to any one of <1> to <8>, contained in a container.
<10> Stimulation is applied to the ink composition in the ink media set according to any one of <1> to <8>, and the ink composition is allowed to fly to form an image on the recording medium in the ink media set. An ink jet recording method comprising at least an ink flying step for recording.
<11> The inkjet recording method according to <10>, wherein the stimulus is at least one selected from heat, pressure, vibration, and light.
<12> Stimulation is applied to the ink composition in the ink media set according to any one of <1> to <8>, and the ink composition is allowed to fly to form an image on the recording medium in the ink media set. An ink jet recording apparatus comprising at least ink flying means for recording.
<13> The inkjet recording apparatus according to <12>, wherein the stimulus is at least one selected from heat, pressure, vibration, and light.
<14> An image recorded using the ink composition in the ink media set on the recording medium in the ink media set according to any one of <1> to <8>. It is an ink recorded matter.

The ink media set of the present invention is an ink media set having an ink composition and a recording medium, and the ink composition includes polymer fine particles including dye and inorganic pigment particles, a water-soluble solvent, water, and the like. The surface tension at 25 ° C. is 20 to 35 mN / m, and the recording medium has a support and a coating layer on at least one surface of the support, Of pure water to the recording medium at a contact time of 100 ms measured with a dynamic scanning absorption meter is 2 ml / m ² or more and less than 35 ml / m ² and the pure water has a contact time of 400 ms. The transfer amount is 3 ml / m ² or more and less than 40 ml / m ² .
In the ink media set of the present invention, it is possible to obtain a high quality image with high saturation and good color tone. That is, by using a dye, it is possible to obtain a vivid image with better color developability compared to pigments on plain paper or dedicated recording paper, and by including inorganic pigment particles, a vivid image with further improved color developability can be obtained. An image can be obtained, and not only the gas resistance is improved by including dye and inorganic pigment particles in the polymer, but the transfer amount of pure water to the recording medium at a contact time of 100 ms is 2 ml / m ² or more. 35 ml / ^m is less than ^2, and the image in low recording medium having ink absorption properties, such as transfer amount is less than 3 ml / ^{m 2} or more 40 ml / ^{m 2} to the recording medium of pure water at the contacting time 400ms Once formed, it can provide an ink media set that does not sink images like water-based dye inks and can form images with higher color development than pigment inks. The
Furthermore, the surface tension at 25 ° C. of the ink composition is set to 20 to 35 mN / m for the point that drying on the recording medium with low ink absorbency is slow and it takes time to set the colorant. It is possible to provide an ink media set in which occurrence of beading is suppressed and high-definition and high-quality image formation is possible.

The ink jet recording method of the present invention includes an ink flying step of applying an stimulus to the ink composition in the ink media set of the present invention and causing the ink composition to fly to record an image on a recording medium in the ink media set. An ink jet recording method comprising:
The ink jet recording method of the present invention forms a high-quality image with high saturation and good color tone by performing printing by attaching the ink composition of the ink media set of the present invention to the recording medium of the ink media set. It is possible to provide an ink jet recording method that enables the above-described method.

The ink jet recording apparatus of the present invention comprises an ink flying means for applying a stimulus to the ink composition in the ink media set of the present invention and causing the ink composition to fly to record an image on a recording medium in the ink media set. An ink jet recording apparatus comprising at least the ink jet recording apparatus.
The ink jet recording apparatus of the present invention has means for recording an image on a recording medium in the ink media set using the ink composition in the ink media set of the present invention, so that the saturation is high and the color tone is high. An ink jet recording apparatus capable of forming a quality image can be provided.

The ink recorded matter of the present invention comprises an image recorded using the ink composition in the ink media set on the recording medium in the ink media set of the present invention. It is.
The ink recorded matter of the present invention can be provided using the ink media set of the present invention to provide a highly saturated and high quality recorded matter.

  According to the present invention, ink media that can solve various problems in the past and have high chroma and high-quality images with good color tone not only on plain paper and inkjet recording paper but also on recording media with low ink absorbency. An ink cartridge, an ink jet recording method, an ink jet recording apparatus, and an ink recorded product using the ink media set can be provided.

(Ink media set)
The ink media set of the present invention comprises an ink composition and a recording medium, and further comprises other configurations as necessary.

The ink composition contains fine polymer particles including dyes and inorganic pigment particles, a water-soluble solvent, and water, and has a surface tension at 25 ° C. of 20 to 35 mN / m.
The recording medium has a support and a coating layer on at least one surface of the support, and pure water is applied to the recording medium at a contact time of 100 ms measured with a dynamic scanning absorptiometer. The transfer amount is 2 ml / m ² or more and less than 35 ml / m ² , and the transfer amount of pure water to the recording medium at a contact time of 400 ms is 3 ml / m ² or more and less than 40 ml / m ² .
The ink media set of the present invention comprises the ink composition and the recording medium, so that the saturation of not only plain paper and inkjet recording paper but also recording media with low ink absorbency is achieved. A high-quality image with high and good color tone can be obtained.

<Ink composition>
The ink composition includes at least polymer fine particles including dyes and inorganic pigment particles, a water-soluble solvent, and water, and further includes a penetrating agent and, if necessary, other components.

The surface tension of the ink composition is 20 to 35 mN / m at 25 ° C., and preferably 24 to 30 mN / m. When the surface tension is in the range of 20 to 35 mN / m, the occurrence of beading is suppressed, and an ink media set capable of forming a high-definition and high-quality image can be provided.
The beading means that an ink droplet at the time of ink jet recording is not absorbed into the recording medium after the ink droplet is hit on the surface of the recording medium until the next ink droplet is hit. This is a phenomenon in which the color material in the ink partially remains agglomerated by mixing with ink droplets that remain in a liquid state on the surface and are hit later, resulting in uneven density. This phenomenon is related to the amount of ink composition absorbed in the recording medium in the recent general printers up to a relatively short time of the contact time up to 100 ms. Absorption of Y ink (or C ink) into the recording medium from when (Y) ink (or cyan (C) ink) is applied to when C ink (or Y ink) is applied The degree of beading changes depending on the amount (transfer amount).
The method for measuring the surface tension is not particularly limited and can be appropriately selected from known ones. A platinum plate is prepared using a surface tension measuring device (CBVP-Z, manufactured by Kyowa Interface Science Co., Ltd.). The method of using and measuring at 25 degreeC etc. are mentioned.

  The viscosity of the ink composition is preferably 5 to 50 mPa · s at 25 ° C. If the viscosity is less than 5 mPa · s, the ink droplets on the recording medium are too large, and therefore beading may occur or color bleeding may occur. If the viscosity exceeds 50 mPa · s, the ink droplets And the nozzles that do not eject ink droplets are also generated, which may disturb the image.

-Polymer fine particles including dye and inorganic pigment particles-
The polymer fine particles including the dye and the inorganic pigment particles indicate at least one of a polymer fine particle in which a dye and an inorganic pigment particle are encapsulated and a polymer fine particle in which an inorganic pigment particle is encapsulated and a dye adsorbed on the surface.
The volume average particle size of the polymer fine particles including the dye and the inorganic pigment particles is, for example, preferably 5 to 200 nm, more preferably 50 to 150 nm. When the volume average particle size is less than 5 nm, it becomes difficult to keep the dispersion state stable, and thus aggregation of the particles and accompanying increase in viscosity may occur. May end up.

--- Dye--
The dye is not particularly limited as long as it can be encapsulated or adsorbed in the polymer fine particles, and can be appropriately selected according to the purpose.
As the dye, an oil-soluble dye and a disperse dye that are water-insoluble are preferable in that they have better encapsulating property and adsorptivity.
The water-insoluble means that the dye does not dissolve 10 parts by mass or more with respect to 100 parts by mass of water at 20 ° C.

  Examples of the pre-oil-soluble dye include a yellow oil-soluble dye, an orange oil-soluble dye, a red oil-soluble dye, a purple oil-soluble dye, a blue oil-soluble dye, a green oil-soluble dye, and a black oil-soluble dye.

  Examples of the yellow oil-soluble dye include C.I. I. Solvent Yellow 5, C.I. I. Solvent Yellow 6, C.I. I. Solvent Yellow 14, C.I. I. Solvent Yellow 16, C.I. I. Solvent Yellow 21, C.I. I. Solvent Yellow 29, C.I. I. Solvent Yellow 33, C.I. I. Solvent Yellow 93, C.I. I. Solvent Yellow 114, C.I. I. Solvent Yellow 151, C.I. I. Solvent Yellow 157, and the like.

  Examples of the orange oil-soluble dye include C.I. I. Solvent Orange 2, C.I. I. Solvent Orange 7, C.I. I. Solvent Orange 55, C.I. I. Solvent orange 60, etc. are mentioned.

  Examples of the red oil-soluble dye include C.I. I. Solvent Red 1, C.I. I. Solvent Red 3, C.I. I. Solvent Red 8, C.I. I. Solvent Red 18, C.I. I. Solvent Red 23, C.I. I. Solvent Red 24, C.I. I. Solvent Red 27, C.I. I. Solvent Red 43, C.I. I. Solvent Red 48, C.I. I. Solvent Red 49, C.I. I. Solvent Red 51, C.I. I. Solvent Red 52, C.I. I. Solvent Red 109, C.I. I. Solvent Red 111, C.I. I. Solvent Red 122, C.I. I. Solvent Red 125, C.I. I. Solvent Red 127, C.I. I. Solvent Red 130, C.I. I. Solvent Red 132, C.I. I. Solvent Red 135, C.I. I. Solvent Red 145, C.I. I. Solvent Red 146, C.I. I. Solvent Red 149, C.I. I. Solvent Red 150, C.I. I. Solvent Red 151, C.I. I. Solvent Red 155, C.I. I. Solvent Red 168, C.I. I. Solvent Red 176, C.I. I. Solvent Red 179, C.I. I. Solvent Red 180, C.I. I. Solvent Red 181, C.I. I. Solvent Red 195, C.I. I. Solvent Red 207, C.I. I. Solvent Red 218, C.I. I. Solvent Red 225, C.I. I. Solvent Red 233, and the like.

  Examples of the purple oil-soluble dye include C.I. I. Solvent Violet 13, C.I. I. Solvent Violet 31, C.I. I. Solvent Violet 36, C.I. I. Solvent Violet 37, C.I. I. Solvent Violet 57, C.I. I. Solvent violet 59, and the like.

  Examples of the blue oil-soluble dye include C.I. I. Solvent Blue 14, C.I. I. Solvent Blue 25, C.I. I. Solvent Blue 35, C.I. I. Solvent Blue 36, C.I. I. Solvent Blue 38, C.I. I. Solvent Blue 44, C.I. I. Solvent Blue 63, C.I. I. Solvent Blue 67, C.I. I. Solvent Blue 70, C.I. I. Solvent Blue 78, C.I. I. Solvent Blue 83, C.I. I. Solvent Blue 87, C.I. I. Solvent Blue 94, C.I. I. Solvent Blue 104, C.I. I. Solvent Blue 105, C.I. I. Solvent Blue 132, C.I. I. Solvent blue 136, and the like.

  Examples of the green oil-soluble dye include C.I. I. Solvent Blue 3, C.I. I. Solvent Blue 5, C.I. I. Solvent Blue 7, C.I. I. Solvent Blue 20, C.I. I. Solvent Blue 28, and the like.

  Examples of the black oil-soluble dye include C.I. I. Solvent Black-3, C.I. I. Solvent Black-27, etc. are mentioned.

  Examples of the pre-oil disperse dye include a yellow disperse dye, an orange disperse dye, a red disperse dye, a purple disperse dye, and a blue disperse dye.

  Examples of the yellow disperse dye include C.I. I. Disperse Yellow 54, C.I. I. Disperse Yellow 64, C.I. I. Disperse Yellow 114, C.I. I. Disperse Yellow 160, and the like.

  Examples of the orange disperse dye include C.I. I. Disperse Orange 30 and the like.

  Examples of the red disperse dye include C.I. I. Disperse thread 22, C.I. I. Disperse thread 60, C.I. I. Disperse thread 73, C.I. I. Disper thread 177, C.I. I. Disperse thread 356, and the like.

  Examples of the purple disperse dye include C.I. I. Disperse violet 57, and the like.

  Examples of the blue disperse dye include C.I. I. Disperse Blue 56, C.I. I. Disperse Blue 60, C.I. I. Disperse Blue 73, C.I. I. Disperse blue 106, C.I. I. Disperse Blue 165, and the like.

As the dye, water-insoluble dyes obtained by water-insolubilizing various water-soluble dyes can also be used.
As a method for insolubilizing the water-soluble dye, for example, a method of forming an ion complex such as binding a cationic surfactant to an anionic dye is preferable.

-Inorganic pigment particles-
The inorganic pigment particles are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include titanium dioxide particles, alumina particles, silica particles, iron oxide particles, iron hydroxide particles, and tin oxide particles. It is done. Among these, titanium oxide particles, alumina particles, and silica particles are particularly preferable.
As the shape of the inorganic pigment particles, those having a small aspect ratio are preferable, and a spherical shape is particularly preferable.
The color of the inorganic pigment particles is preferably transparent or white.
The primary particle diameter of the inorganic pigment particles is preferably 100 nm or less, and more preferably 5 to 50 nm.

--Polymer--
There is no restriction | limiting in particular as a polymer which comprises the polymer microparticles | fine-particles containing the said dye and an inorganic pigment particle, It can select suitably from well-known things, For example, a polyester-type resin, a polyurethane-type resin, a vinyl-type resin, an acrylic resin Resin, epoxy resin, olefin resin, polyimide resin, alkyd resin, fluororesin, silicone resin, and the like. Among these, polyester resins, polyurethane resins, vinyl resins, and acrylic resins are preferable because it is easy to stably disperse the polymer fine particles in the aqueous dispersion medium.

As said polyester-type resin, what consists of polyhydric carboxylic acid and polyhydric alcohol is mentioned, for example.
Examples of the polyvalent carboxylic acids include aromatic dicarboxylic acids and aliphatic dicarboxylic acids.
Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, diphenic acid, sulfoterephthalic acid, 5-sulfoisophthalic acid, Examples include hexahydrophthalic anhydride, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7dicarboxylic acid, 5 [4-sulfophenoxy] isophthalic acid, sulfoterephthalic acid, and the like.
Examples of the aliphatic dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, and the like.
Examples of other polyvalent carboxylic acids include aromatic oxycarboxylic acids, alicyclic dicarboxylic acids, and trivalent or higher polyvalent carboxylic acids.

Examples of the polyhydric alcohols include aliphatic polyhydric alcohols.
Examples of the aliphatic polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 2,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, trimethylolethane, trimethylolpropane, glycerin, penta Erthritol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, spiroglycol, tricyclodecanediol, tricyclodecane dimethanol, metaxylene glycol, orthoxyl Glycol, 1,4-phenylene glycol, bisphenol A, lactone polyester polyols, and the like.
Examples of other polyhydric alcohols include alicyclic polyhydric alcohols and aromatic polyhydric alcohols.

As said polyurethane-type resin, what consists of a compound which has a functional group which can react with isocyanates and isocyanates is mentioned, for example.
Examples of the polyurethane resin include resins obtained by polymerizing the isocyanates and compounds having a functional group capable of reacting with isocyanates alone or in combination of two or more.

Examples of the isocyanates include aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and the like.
Examples of the aliphatic polyisocyanate include ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, and nonamethylene diisocyanate.
Examples of the alicyclic polyisocyanate include isophorone diisocyanate, bis (isocyanatomethyl) cyclohexane, dicyclohexylmethane diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, and dicyclohexyldimethylmethane diisocyanate.
Examples of the aromatic polyisocyanate include phenylene diisocyanate, tolylene diisocyanate, ethylphenylene diisocyanate, isopropylene phenylene diisocyanate, dimethylphenylene diisocyanate, diethylphenylene diisocyanate, diisopropylphenylene diisocyanate, trimethylbenzene triisocyanate, benzene triisocyanate, naphthalene diisocyanate, And methyl naphthalene diisocyanate, biphenyl diisocyanate, and tolidine diisocyanate.
Examples of other isocyanates include sulfur-containing aliphatic isocyanates, aliphatic disulfide-based isocyanates, aromatic sulfone-based isocyanates, sulfonic acid ester-based isocyanates, aromatic sulfonic acid amides, and sulfur-containing heterocyclic compounds.

Examples of the compound having a functional group capable of reacting with the isocyanates include aliphatic polyols, aromatic polyols, and condensation reaction products of organic acids and polyols (at least one of the aliphatic polyols and aromatic polyols). , Etc.
Examples of the aliphatic polyol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, glycerin, trimethylolethane, trimethylolpropane, butanetriol, 1 , 2-methylglycoside, pentaerythritol, dipentaerythritol, tripentaerythritol, sorbitol, erythritol, threitol, ribitol, arabinitol, xylitol, allitol, mannitol, dolitol, iditol, glycol, inositol, hexanetriol, triglycerose, diglycerol , Polyethylene glycol, polypropylene glycol, poly Tetraethylene ether glycol, tris (2-hydroxyethyl) isocyanurate, cyclobutanediol, cyclopentanediol, cyclohexanediol, cycloheptanediol, cyclooctanediol, polylactonediol, cyclohexanedimethanol, hydroxypropylcyclohexanol, dicyclohexanediol, Examples include cyclohexanetriol, maltitol, and lactitol.

  Examples of the aromatic polyol include dihydroxynaphthalene, trihydroxynaphthalene, tetrehydroxynaphthalene, dihydroxybenzene, benzenetriol, biphenyltetraol, pyrogaol, (hydroxynaphthyl) pyrogallol, trihydroxyphenanthrene, bisphenol A, bisphenol F, and xylylene. Glycol, di (2-hydroxyethoxy) benzene, and the like.

  Examples of the organic acid in the condensation reaction product of the organic acid and the polyol include oxalic acid, glutamic acid, adipic acid, acetic acid, phthalic acid, isophthalic acid, salicylic acid, and pyromellitic acid.

  Examples of other compounds having a functional group capable of reacting with the isocyanates include halogenated polyols, addition reaction products of the polyols with alkylene oxides such as ethylene oxide and propylene oxide, addition of alkylene polyamines and alkylene oxides. Reaction product, 2,2-dimethylollactic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolvaleric acid, 3,4-diaminobutanesulfonic acid, 3,6- Examples include diamino-2-toluenesulfonic acid, or a modified product of these caprolactones, a polyamino compound, a polythiol compound, and an α-amino acid. These may be used individually by 1 type and may use 2 or more types together.

  There is no restriction | limiting in particular as said vinyl resin and acrylic resin, Although it can select suitably according to the objective, For example, what consists of a polymerizable monomer mentioned later is mentioned.

Examples of the polymerizable monomer include vinyl aromatic hydrocarbons, (meth) acrylic acid esters, unsaturated carboxylic acids, and the like.
Examples of the vinyl aromatic hydrocarbon include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-tert- Examples include butyl styrene, p-chlorostyrene, divinylbenzene, and the like.
Examples of the (meth) acrylic acid ester include methyl acrylate, ethyl acrylate, butyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, N-pentyl acrylate, isopentyl acrylate, neopentyl acrylate, 3- (methyl) butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, hexyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, Undecyl acrylate, phenyl dodecyl acrylate, methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, methacrylate N-pentyl acid, isopentyl methacrylate, neopentyl methacrylate, 3- (methyl) butyl methacrylate, 2-ethylhexyl methacrylate, hexyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, undecyl methacrylate, methacryl And dodecyl acid.
Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, maleic acid, and the like.
Examples of other polymerizable monomers include (meth) acrylamide, N-substituted maleimide, maleic anhydride, (meth) acrylonitrile, vinyl ketone, vinyl acetate, and vinylidene chloride.
These polymerizable monomers may be used individually by 1 type, and may use 2 or more types together.

The polymer fine particles can exhibit excellent water dispersibility by containing an ionic group on the surface.
Examples of the ionic group include sulfonic acid groups, carboxylic acid groups, sulfuric acid groups, phosphoric acid groups, phosphonic acid groups, and phosphinic acid groups, and alkali metal bases, ammonium bases, or primary to A tertiary amine group, and the like. Among these, alkali metal carboxylate, ammonium carboxylate, alkali metal sulfonate, and ammonium sulfonate are preferable. Furthermore, among these, sulfonic acid alkali metal bases and ammonium sulfonate bases are more preferable from the viewpoint of excellent water dispersion stability.
The introduction of the ionic group is performed by adding a monomer having an ionic group during resin synthesis.
Examples of the salt in the ionic group include ammonium ions, Li, Na, K, Mg, Ca, Cu, Fe, and the like. Among these, Li, K, and Na are more preferable because they do not generate gas and are difficult to form precipitates.

The method for producing fine particles by coating the dye and inorganic pigment particles with a polymer is not particularly limited and can be appropriately selected from known ones, such as an interfacial deposition method and an interfacial polymerization method. It is done.
Among the interfacial deposition methods, methods used particularly for inkjet include a phase inversion emulsification method and an acid precipitation method.
In the phase inversion emulsification method, a polymer and a water-insoluble dye are dispersed in an organic solvent having a low compatibility with water and having a boiling point lower than that of water. After the polymer is hydrophilized, water is added to emulsify the organic solvent. It is a method of phase inversion to water system by leaving.
In the acid precipitation method, a polymer and a water-insoluble dye are dispersed in an aqueous system, and an acid is added to hydrophobize the polymer so that the polymer is strongly adsorbed on the water-insoluble dye particles. This is a method of dispersing in an aqueous system.
As a specific method of acid precipitation, first, a basic compound is added to neutralize acidic groups such as carboxyl groups to dissolve a hydrophilic polymer in an aqueous medium, and then a pigment is added to the solution. After moistening, the pigment particles are made into a polymer by high-speed stirring using a homogenizer, a kneading and dispersing machine using balls such as a bead mill and a ball mill, a kneading and dispersing machine using shearing force such as a roll mill, and an ultrasonic dispersing machine. Disperse in an aqueous medium in a rare state.
Examples of the basic compound include inorganic salts such as sodium hydroxide, potassium hydroxide and lithium hydroxide, and organic amines such as diethanolamine, dimethylethanolamine, triethanolamine and diisopropanolamine.
As the dispersion aid, a surfactant can be added, but it is necessary to keep the amount as small as possible within a range in which print quality and water resistance are not deteriorated.
Next, an acid is added to the obtained dispersion to oxidize the carboxyl group to insolubilize it in water, and the polymer is precipitated on the pigment particles to be more strongly adsorbed. At this time, the pigment particles settle in a paste form on the bottom of the aqueous medium.
Examples of the acid include inorganic acids and organic acids.
Examples of the inorganic acid include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and the like.
Examples of the organic acid include formic acid and acetic acid.
The pH after the acid precipitation is preferably in the range of 2-6.
The acid is preferably added in such a range that the polymer is not altered by the acid.
In order to neutralize the paste and separate the paste and water, suction filtration, pressure filtration, and centrifugation are used.
Next, a basic substance is added to the neutralized paste to make it hydrophilic again and dispersed in an aqueous medium.
Examples of the basic substance include the inorganic salts and the organic amines.

Among the interfacial polymerization methods, an emulsion polymerization method can be suitably used, and is carried out in an inert solvent such as ion-exchanged water in the presence of a polymerization initiator.
Examples of the polymerization initiator include persulfates, perborates, and redox polymerization initiators that use a peroxide and a reducing agent in combination.
Examples of the persulfate include potassium persulfate, sodium persulfate, and ammonium persulfate.
Examples of the perborate include sodium perborate, potassium perborate, and ammonium perborate.
Examples of the peroxide in the redox polymerization initiator include the persulfate and the perborate.
Examples of the reducing agent in the redox polymerization initiator include sodium sulfite, sodium thiosulfate, and ferrous sulfate.
The reaction temperature in the emulsion polymerization method can be appropriately selected according to the type of reactant, the type of solvent, and the like, and is preferably room temperature (20 ° C.) to 100 ° C., for example.
The reaction time in the emulsion polymerization method can be appropriately selected according to the type of reactant, the type of solvent, and the like, and is preferably, for example, 3 hours to 20 hours.
After the reaction in the emulsion polymerization method is completed, an emulsifier-containing polymer emulsion is obtained by a usual means such as neutralization.

The content of the dye in the polymer fine particles including the dye and the inorganic pigment particles is preferably 10 to 80% by mass and more preferably 20 to 60% by mass with respect to the total solid content of the polymer fine particles. When the content is less than 10% by mass, the saturation and image density of the ink recorded matter may not be sufficiently obtained. When the content exceeds 80% by mass, the storage stability of the ink is deteriorated. There is. The content of the inorganic pigment particles in the polymer fine particles including the dye and the inorganic pigment particles is preferably 5 to 60% by mass and more preferably 10 to 40% by mass with respect to the total solid content of the polymer fine particles.
The solid content of the fine polymer particles including the dye and the inorganic pigment particles is preferably 2 to 40% by mass and more preferably 5 to 20% by mass with respect to the total solid content of the ink composition.

-Water-soluble solvent-
The water-soluble solvent is for preventing the drying of the ink composition using water as a liquid medium, and for improving the dispersion stability.
Examples of the water-soluble solvent include polyhydric alcohols, polyhydric alcohol alkyl ethers, polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, sulfur-containing compounds, propylene carbonate, and ethylene carbonate. , Etc. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the polyhydric alcohols include glycerin, diethylene glycol, 1,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, propylene glycol, dipropylene glycol, trimethylolpropane, and trimethylolethane. , Ethylene glycol, diethylene glycol, dipropylene glycol, tripropylene glycol, tetraethylene glycol, hexylene glycol, polyethylene glycol, polypropylene glycol, 1,5-pentanediol, 1,6-hexanediol, glycerol, 1,2,6- Examples include hexanetriol, 1,2,4-butanetriol, 1,2,3-butanetriol, and petriol.

  Examples of the polyhydric alcohol alkyl ethers include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl ether, and the like. Can be mentioned.

  Examples of the polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

  Examples of the nitrogen-containing heterocyclic compound include 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, ε-caprolactam, γ-butyrolactone, Etc.

  Examples of the amides include formamide, N-methylformamide, N, N-dimethylformamide, and the like.

  Examples of the amines include monoethanolamine, diethanolamine, triethanolamine, monoethylamine, diethylamine, triethylamine, and the like.

  Examples of the sulfur-containing compounds include dimethyl sulfoxide, sulfolane, thiodiethanol, and the like.

  Among these, glycerin, diethylene glycol, triethylene glycol, 1, 3 are excellent in terms of solubility and prevention of poor jetting characteristics due to water evaporation, and excellent storage stability and ejection stability. -Butanediol, 1,6-hexanediol, propylene glycol, 1,5-pentanediol, dipropylene glycol, trimethylolpropane and 3-methyl-1,3-butanediol are preferred.

The water-soluble solvent preferably contains a saccharide.
Examples of the saccharide include monosaccharides, disaccharides, oligosaccharides (including trisaccharides and tetrasaccharides), and polysaccharides.
Specific examples of the saccharide include glucose, mannose, fructose, ribose, xylose, arabinose, galactose, maltose, cellobiose, lactose, sucrose, trehalose, maltotriose, and the like.
The polysaccharide means a saccharide in a broad sense and can be used to include substances widely existing in nature such as α-cyclodextrin and cellulose.
Examples of the saccharide include derivatives of the saccharide.
Examples of the saccharide derivative include reducing sugar, oxidized sugar, amino acid, thioic acid, and the like of the saccharide.
Examples of the reducing sugar include sugar alcohols. Examples of the sugar alcohol include compounds represented by the following general formula (9). Specific examples of the sugar alcohol include maltitol and sorbit.
HOCH ₂ (CHOH) nCH ₂ OH... General formula (9)
However, in general formula (9), n represents the integer in any one of 2-5.
Examples of the oxidized sugar include aldonic acid and uronic acid.
Among these, sugar alcohol is preferable.

The content of the water-soluble solvent is preferably 10 to 50% by mass with respect to the total amount of the ink composition. When the content is less than 10% by mass, the ink in the nozzle tends to dry, and thus the ejected ink droplets may not fly straight, or may not be ejected due to increased viscosity. . Ink storage stability may deteriorate.
The value of the solid content ratio of polymer fine particles including the water-soluble solvent and the dye and inorganic pigment particles (mass of the water-soluble solvent / solid content mass of the polymer fine particles including the dye and inorganic pigment particles) is determined from the head. This greatly affects the ink ejection stability. If the solid content of the polymer fine particles including the dye and inorganic pigment particles is high but the amount of the wetting agent is small, water evaporation near the ink meniscus of the nozzle may progress and cause ejection failure.
The solid content ratio of polymer fine particles including the water-soluble solvent and the dye and inorganic pigment particles (mass of the water-soluble solvent / solid content mass of the polymer fine particles including the dye and inorganic pigment particles) is, for example, It is preferably 0.25 to 25, more preferably 1 to 8, and particularly preferably 2 to 4. When the solid content ratio of the water-soluble solvent and the polymer fine particles including the dye and the inorganic pigment particles is within the range, the ink composition has very good drying properties, storage stability, and reliability.

-Penetration agent-
By adding the penetrant to the ink composition, the surface tension is reduced, and the ink penetrates into the recording medium after landing on the recording medium such as paper. Can be reduced.
The penetrant is not particularly limited as long as the surface tension of the ink composition is in the range of 20 to 35 mN / m, and the dispersion stability is not impaired by a combination of the kind of the dye and the water-soluble solvent. Surfactant is mentioned.
Examples of the penetrant include anionic surfactants and nonionic surfactants.

  Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, laurate, polyoxyethylene alkyl ether sulfate salt, and fluorine surfactant.

  Examples of the nonionic surfactant include polyol, glycol ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylphenyl ether, polyoxyethylene alkylamine, polyoxyethylene Examples thereof include ethylene alkylamide, acetylene glycol, and a fluorosurfactant.

Examples of the acetylene glycol surfactants include 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1-hexyn-3-ol, and the like.
A commercially available thing can be used as said acetylene glycol type surfactant. Examples of the commercially available acetylene glycol surfactant include Surfynol 104, 82, 465, 485, and TG manufactured by Air Products (USA). Among these, Surfynol 465, 104, and TG are preferable in terms of showing good print quality.

Examples of the fluorosurfactant include perfluoroalkyl sulfonate, perfluoroalkyl carboxylate, perfluoroalkyl phosphate, perfluoroalkyl ethylene oxide adduct, perfluoroalkyl betaine, and perfluoroalkylamine oxide. And perfluoroalkyl ether compounds.
A commercially available thing can be used as said fluorosurfactant.
Examples of the commercially available fluorosurfactant include Surflon S-111, S-112, S-113, S121, S131, S132, S-141, S-145 manufactured by Asahi Glass Co., Ltd .; manufactured by Sumitomo 3M Limited. Fullrad FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431; Daifuku Ink Chemical Co., Ltd. MegaFuck F-470, F -1405, F-474; DuPont Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR; FT-110, 250, 251, 400S made by Neos Co., Ltd. Can be mentioned. These surfactants may be used alone or in combination of two or more.

Specific examples of the penetrant include compounds represented by the following formula.
In the general formula (1), ^{R 2} represents an alkyl group having 6 to 14 carbon atoms. The alkyl group may be branched. M ² represents any one of an alkali metal, a quaternary ammonium, a quaternary phosphonium, and an alkanolamine. m represents an integer of 3 to 12.
However, In the general formula (2), R ³ represents an alkyl group having 5 to 16 carbon atoms. The alkyl group may be branched. M ³ represents any one of an alkali metal, a quaternary ammonium, a quaternary phosphonium, and an alkanolamine.
However, in said general formula (3), R represents a C6-C14 hydrocarbon group. The hydrocarbon group may be branched. k represents an integer of 5 to 20.
In the general formula (4), R ⁵ represents a hydrocarbon group having 6 to 14 carbon atoms. The hydrocarbon group may be branched. l represents an integer of 5 to 20.
However, in said general formula (5) and (6), R 'is mutually independent and represents a C6-C14 hydrocarbon group. m and n are independent of each other and represent an integer of 20 or less.
However, in the said General formula (7), p and q are mutually independent and represent the integer in any one of 0-40.
However, in the said General formula (9), Rf1 represents either of following formula (8) -1 and following formula (8) -2.

As the penetrant, a water-soluble organic solvent such as a polyol compound or a glycol ether compound is preferably used. Among these, it is more preferable to use at least one of a polyol compound having 8 or more carbon atoms and a glycol ether compound.
When the polyol compound has less than 8 carbon atoms, sufficient penetrability cannot be obtained, and the recording medium is soiled at the time of double-sided printing, or the ink composition does not spread sufficiently on the recording medium and the pixel is buried. May deteriorate character quality and image density.
Examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol (solubility: 4.2% (25 ° C.)), 2,2,4-trimethyl-1,3-pentanediol. (Solubility: 2.0% (25 ° C.)) is preferable.

  The glycol ether compound is not particularly limited and may be appropriately selected depending on the intended purpose.For example, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, Examples include polyhydric alcohol alkyl ethers such as tetraethylene glycol monomethyl ether and propylene glycol monoethyl ether; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

  The amount of the penetrant added is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 0.1 to 10% by mass, and preferably 1 to 5% by mass with respect to the total amount of the ink composition. Is more preferable.

-Other ingredients-
Examples of the other components include pH adjusters, antiseptic / antifungal agents, rust inhibitors, kogation inhibitors, water-soluble ultraviolet absorbers, and water-soluble infrared absorbers.

-PH adjuster-
The pH adjusting agent can stabilize the dispersion state and keep the ejection stable by keeping the ink composition alkaline.
If the ink composition has a pH of 11 or more, the amount of the ink jet head and the ink supply unit that melts out is large, and problems such as ink deterioration, leakage, and poor discharge may occur.
As a method of adding the pH adjuster, a method of adding a dye when kneaded and dispersed in water together with a dispersant is preferable to a method of adding the additive together with a water-soluble solvent and a penetrant after kneading and dispersing. This is because the dispersion of the pH adjusting agent may be destroyed by adding depending on the type.

Examples of the pH adjuster include alcohol amines, alkali metal hydroxides, ammonium hydroxides, phosphonium hydroxides, and alkali metal carbonates. These may be used individually by 1 type and may use 2 or more types together.
Examples of the alcohol amines include diethanolamine, triethanolamine, 2-amino-2-ethyl-1,3-propanediol, and the like.
Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, and the like.
Examples of the ammonium hydroxide include ammonium hydroxide and quaternary ammonium hydroxide.
Examples of the phosphonium hydroxide include quaternary phosphonium hydroxide.
Examples of the alkali metal carbonate include lithium carbonate, sodium carbonate, and potassium carbonate.

-Antiseptic and fungicide-
Examples of the antiseptic / antifungal agent include sodium dehydroacetate, sodium sorbate, 2-pyridinethiol-1-oxide sodium, sodium benzoate, sodium pentachlorophenol, and the like.

-Chelating reagent-
Examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, sodium uramil diacetate, and the like.

-Antirust agent-
Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.

-Kogation inhibitor-
By containing the anti-kogation agent in the ink composition, kogation can be prevented.
The kogation is a problem in a thermal head in which an ink composition is instantaneously heated by passing an electric current through a heater, and the ink composition is ejected by utilizing a foaming force of the ink composition. This is a phenomenon in which when an ink is heated, the components of the ink composition change in quality and the deteriorated material adheres to the heater. When the kogation occurs, heating by the heater is not normally performed, and the ejection force may be weakened, or in the worst case, the ink composition may not be ejected.
Examples of the kogation inhibitor include polyphosphoric acid, polyaminocarboxylic acid, aldonic acid, hydroxycarboxylic acid, polyol phosphoric acid ester, and salts thereof, any of acids having an amino group and salts thereof, methyl group or methylene group. An ammonium salt of an acid having a group and a carboxyl group.

Examples of the polyphosphoric acids include pyrophosphoric acid, tripolyphosphoric acid, hexametaphosphoric acid, and the like.
Examples of the polyaminocarboxylic acids include dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, and glutaric acid, ethylenediaminetetraacetic acid, iminodiacetic acid, and nitrilotriacetic acid.
Examples of the aldonic acid include glycolic acid, glyceric acid, gluconic acid, galactonic acid, and glucoheptonic acid.
Examples of the hydroxycarboxylic acids (also known as oxycarboxylic acids) include citric acid, malic acid, lactic acid, glycolic acid, glyceric acid, mandelic acid, tartaric acid, and the like.
Examples of the polyol phosphates include α-glycerophosphoric acid and β-glycerophosphoric acid.
Among these, citric acid, gluconic acid (in solid form, δ-gluconolactone and γ-gluconolactone), malic acid, lactic acid, glycolic acid, tartaric acid, etc. are highly soluble in water. Of these, hydroxycarboxylic acids (also known as oxycarboxylic acids), α-glycerophosphoric acid, β-glycerophosphoric acid and the like are preferable. Furthermore, citric acid and gluconic acid are particularly preferred.
These compounds may be used in acid form or in salt form, and examples thereof include alkali metal salts, ammonium salts, organic amine salts, and the like.
Examples of the organic amine salt include triethanolamine, diethanolamine, monoethanolamine, triisopropanolamine, and the like.
When the salt form is used, a commercially available compound in the salt form may be used as it is, or an alkali agent may be added to prepare a salt form of an organic acid.
Examples of the alkaline agent include lithium hydroxide, sodium hydroxide, potassium hydroxide, aqueous ammonia (ammonium hydroxide), and organic amines (eg, triethanolamine, diethanolamine, monoethanolamine, diisopropanolamine, triisopropanolamine). , Tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, etc.).
As the organic acid salt, for example, an ammonium salt is preferably used.
The said kogation inhibitor may be used individually by 1 type, and may use 2 or more types together.
As content of the said organic acid or its salt, 0.005-20 mass% is preferable with respect to the said ink composition whole quantity, and 0.05-12 mass% is more preferable. When the content is within this range, in the case where it coexists with at least one of an acid having an amino group and a salt thereof, which will be described later, it has an excellent effect of reducing kogation. An ink composition that is unlikely to occur can be obtained.

Examples of the acid having an amino group or an acid thereof having an amino group include amidosulfuric acid (also known as sulfamic acid), aminomethanesulfonic acid, taurine (also known as 2-aminoethanesulfonic acid), carbamic acid, and glycine. , Alanine, aspartic acid, glutamic acid, phenylalanine, leucine, isoleucine, threonine, tryptophan, valine methionine, lysine, and the like.
Among these, a compound having a sulfone group is preferable because of its high solubility in water and high effect of improving the head life as described above.
Specific examples of the compound having a sulfone group include amidosulfuric acid (alias: sulfamic acid), aminomethanesulfonic acid, and taurine (alias: 2-aminoethanesulfonic acid). Of these, taurine (also known as 2-aminoethanesulfonic acid) is preferable because it is easily available.
When using the salt having an amino group, a commercially available compound in a salt form may be used, or a salt form of an organic acid is prepared by adding an alkali agent as listed below. May be.
Examples of the alkaline agent include lithium hydroxide, sodium hydroxide, potassium hydroxide, aqueous ammonia (ammonium hydroxide), and organic amines (eg, triethanolamine, diethanolamine, monoethanolamine, diisopropanolamine, triisopropanolamine). , Tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, etc.).
As specific examples of the salt type of the organic acid, for example, an ammonium salt of an organic acid having an amino group is preferable.
The acid having an amino group or a salt thereof may be used alone or in combination of two or more.
As content of the acid which has the said amino group, or its salt, 0.005-20 mass% is preferable with respect to the said ink composition, for example, and 0.05-12 mass% is more preferable. When the content is within this range, an excellent co-polymer is obtained in the situation where the polyphosphoric acid, the polyaminocarboxylic acid, the aldonic acid, the hydroxycarboxylic acid, the polyol phosphate ester, and salts thereof coexist. It is possible to obtain an ink composition that has a gating reduction effect and is less likely to cause nozzle clogging.

  Content of the polyphosphoric acid, the polyaminocarboxylic acid, the aldonic acid, the hydroxycarboxylic acid, the polyol phosphoric ester, and a salt thereof used as the kogation inhibitor, and an acid having an amino group and a salt thereof As a value of the ratio to the content of (the content of the compound used as the kogation inhibitor / the content of the acid having an amino group and the salt thereof), 20/1 to 1/20 is preferable. When the value of the ratio is within this range, the effect of reducing the adhesion of kogation to the heater is sufficiently exhibited, and damage to the outermost protective layer of the heater can be suppressed extremely effectively.

The ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group is preferably one that hardly visually affects the color tone of the ink composition. That is, the acid having a methyl group or a methylene group and a carboxyl group is preferably one whose aqueous solution is not visually colored at least.
The acid having a methyl group or methylene group and a carboxyl group is preferably, for example, one having 10 or less carbon atoms in one molecule and 3 to 6 oxygen atoms in one molecule.
Examples of the acid having a methyl group or a methylene group and a carboxyl group include malonic acid, succinic acid, glutaric acid, adipic acid, lactic acid, malic acid, aspartic acid, glutamic acid and the like.

The acid ammonium salt having a methyl group or a methylene group and a carboxyl group may be used alone or in combination of two or more.
The content of the ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group is preferably 0.005 to 20% by mass and more preferably 0.05 to 15% by mass with respect to the total amount of the ink composition. . When the content is within this range, it is possible to obtain an ink composition excellent in the effect of sufficiently reducing kogation and ink jet aptitude (such as difficulty in clogging an ink jet recording head).

In the ink composition, the phosphorus concentration in the ink composition can be adjusted in order to prevent kogation.
When the phosphorus concentration is 500 ppm or less, the occurrence of kogation can be effectively suppressed even after the ink composition has been stored for a long period of time, and the ink composition exhibits stable ejection characteristics, resulting in high quality. A stable image can be obtained stably.
When the phosphorus concentration is high (over 500 ppm), the mechanism of promoting kogation formation on the heater and rapidly reducing the discharge amount can be considered as follows.
The inorganic phosphorus compound in the ink composition is heated by a heater in a nozzle to form calcium and a compound eluted in the ink composition or from an ink-contacting material such as a nozzle or a tank. Adhere to. The compound of phosphorous compound and calcium (for example, calcium phosphate, hydroxyapatite, etc.) is very hard and hardly soluble, and is not re-decomposed or peeled off. The burn of the re-dispersed pigment ink tends to adhere to the heater. Thus, it is considered that carbon scorch deposition that does not occur in the absence of kogation due to the phosphorus compound occurs at an accelerated rate, the foaming is inhibited, and the discharge amount is rapidly reduced. Although it is not clear why the burning of carbon is promoted by a small amount of phosphorus compound and calcium, the burning of the phosphorous compound and calcium causes fine irregularities on the heater, which causes carbon burning. Presumably because of entering.

<Recording media>
The recording medium includes a support and a coating layer on at least one surface of the support, and further includes other layers as necessary.

The transfer amount of pure water to the recording medium at a contact time of 100 ms measured with a dynamic scanning absorption meter in the recording medium is 2 ml / m ² or more and less than 35 ml / m ² , and 2.5 to 15 ml. / M ² is preferred. If the transfer amount of pure water at the contact time of 100 ms is less than 2 ml / m ² , beading is likely to occur. If it is 4 ml / m ² or more, the ink dot diameter after recording is desired. It may be too smaller than the diameter.
The transfer amount of pure water to the recording medium at a contact time of 400 ms measured with a dynamic scanning absorption meter in the recording medium is 3 ml / m ² or more and less than 40 ml / m ² , and 3.5 to 25 ml. / M ² is more preferable. If the transfer amount at the contact time of 400 ms is less than 3 ml / m ² , the drying property is insufficient, and thus spur marks may be easily generated. If the contact amount is 5 ml / m ² or more, the image after drying The gloss of the part may tend to be low.

  Here, the dynamic scanning absorptiometer (DSA, Papa-Pagi Technical Journal, Vol. 48, May 1994, pp. 88-92, Kuju Shigenori) absorbs liquid in a very short time. It is a device that can measure accurately. The dynamic scanning absorption meter reads the liquid absorption speed directly from the movement of the meniscus in the capillary, makes the sample a disk, and then scans the liquid absorption head in a spiral shape, and the scanning speed according to a preset pattern. Is automatically changed by a method in which the number of necessary points is measured with one sample. A liquid supply head for a paper sample is connected to a capillary via a Teflon (registered trademark) tube, and the position of the meniscus in the capillary is automatically read by an optical sensor. Specifically, the transfer amount of pure water was measured using a dynamic scanning absorption meter (K350 series D type, manufactured by Kyowa Seiko Co., Ltd.). The transfer amount at the contact time of 100 ms and the contact time of 400 ms can be obtained by interpolation from the measured value of the transfer amount at the contact time adjacent to each contact time.

-Support-
The support is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include paper based on wood fibers, and sheet-like materials such as nonwoven fabrics mainly composed of wood fibers and synthetic fibers. It is done.

There is no restriction | limiting in particular as said paper, According to the objective, it can select suitably according to the objective, For example, wood pulp, waste paper pulp, etc. are used. Examples of the wood pulp include hardwood bleached kraft pulp (LBKP), softwood bleached kraft pulp (NBKP), NBSP, LBSP, GP, and TMP.
Examples of the raw material of the used paper pulp include, as shown in the used paper standard quality standard table of the used paper recycling promotion center, white, ruled white, cream white, card, white, medium white, imitation, fair white, Kent , White art, special upper limit, another upper limit, newspaper, magazine and so on. Specifically, printer paper such as non-coating computer paper, thermal paper, and pressure-sensitive paper as information-related paper; OA waste paper such as PPC paper; coating of art paper, coated paper, finely coated paper, matte paper, etc. Paper: High quality paper, color quality, notebook, notepaper, wrapping paper, fancy paper, medium quality paper, newsprint, reprint paper, super paper, imitation paper, pure white roll paper, uncoated paper such as milk carton, etc. Examples of used paper and paperboard include chemical pulp paper and high-yield pulp-containing paper. These may be used individually by 1 type and may use 2 or more types together.

The waste paper pulp is generally produced from a combination of the following four steps.
(1) For disaggregation, waste paper is treated with mechanical force and chemicals with a pulper to loosen it into a fibrous form, and the printing ink is peeled off from the fiber.
(2) Dust removal is to remove foreign matter (plastic etc.) and dust contained in waste paper with a screen, cleaner or the like.
(3) In the deinking, the printing ink peeled off from the fiber using a surfactant is removed from the system by a flotation method or a cleaning method.
(4) Bleaching increases the whiteness of the fiber using an oxidizing action or a reducing action.

  The mixing ratio of the used paper pulp in the case of mixing the used paper pulp is preferably 40% by mass or less with respect to the total solid content of the whole pulp. When the mixing ratio is 40% by mass or less, curling of the recording medium after recording can be suppressed.

As the internal filler used for the support, for example, a conventionally known pigment is used as a white pigment.
Examples of the white pigment include light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, White inorganic pigments such as calcium silicate, magnesium silicate, synthetic silica, aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide; styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin And organic pigments such as melamine resin. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the internally added sizing agent used for making the support include neutral rosin sizing agents used for neutral papermaking, alkenyl succinic anhydride (ASA), alkyl ketene dimer (AKD), and petroleum resins. System sizing agents and the like. Among these, a neutral rosin sizing agent or alkenyl succinic anhydride is particularly preferable. The alkyl ketene dimer may be added in a small amount because of its high size effect, but the friction coefficient on the surface of the recording paper (media) is low and slippery, which is not preferable from the viewpoint of transportability during ink jet recording. There is.

-Coating layer-
The coating layer contains a pigment and a binder, and further contains a surfactant and other components as necessary.

Examples of the pigment include a combination of an inorganic pigment, an inorganic pigment, and an organic pigment.
Examples of the inorganic pigment include kaolin, talc, heavy calcium carbonate, light calcium carbonate, calcium sulfite, amorphous silica, titanium white, magnesium carbonate, titanium dioxide, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, Examples thereof include zinc hydroxide and chlorite.
Among these, kaolin is particularly preferable because it is excellent in gloss expression and can have a texture close to that of paper for offset printing.
Examples of the kaolin include delaminated kaolin, calcined kaolin, engineered kaolin by surface modification, and the like.
As the kaolin, the content of kaolin having a particle size distribution with a particle size of 2 μm or less being 80% by mass or more is preferably 50% by mass or more based on the total solid content of kaolin.
The kaolin content is preferably 50 parts by mass or more with respect to 100 parts by mass of the binder. When the content is less than 50 parts by mass, a sufficient effect may not be obtained in glossiness.
The upper limit of the content is not particularly limited, but is preferably 90 parts by mass or less from the viewpoint of coating suitability in consideration of the fluidity of kaolin, particularly thickening under high shear force.

Examples of the organic pigment include water-soluble dispersions such as styrene-acrylic copolymer particles, styrene-butadiene copolymer particles, polystyrene particles, and polyethylene particles. These may be used individually by 1 type and may use 2 or more types together.
As content of the said organic pigment, 2-20 mass parts is preferable with respect to 100 mass parts of all the pigments in the said coating layer.
As an effect of the organic pigment, because it is excellent in gloss development and its specific gravity is smaller than that of an inorganic pigment, it is bulky, high gloss, and obtains a coating layer with good surface coverage, Etc.
When the content of the organic pigment is less than 2 parts by mass, the above effect is not achieved. When the content exceeds 20 parts by mass, the fluidity of the coating liquid deteriorates, leading to a decrease in coating operability, and the cost. It is not economical.

  There is no restriction | limiting in particular as a form of the said organic pigment, According to the objective, it can select suitably, For example, a solid type, a hollow type, a donut type, etc. are mentioned. Among these, a hollow mold having a porosity of 40% or more is preferable from the viewpoint of balance between glossiness, surface coverage, and fluidity of the coating liquid. In addition, the average particle diameter of the organic pigment is preferably 0.2 to 3.0 μm from the viewpoint of the balance of gloss expression, surface coverage, and fluidity of the coating liquid, for example.

There is no restriction | limiting in particular as said binder, According to the objective, it can select suitably, For example, an aqueous polymer is preferable.
Examples of the aqueous polymer include water-soluble polymers and water-dispersible polymers. These may be used individually by 1 type and may use 2 or more types together.

There is no restriction | limiting in particular as said water-soluble polymer, According to the objective, it can select suitably, For example, modified products of polyvinyl alcohol, such as polyvinyl alcohol, anion modified polyvinyl alcohol, cation modified polyvinyl alcohol, acetal modified polyvinyl alcohol; Polyurethane; polyvinylpyrrolidone and polyvinylpyrrolidone and vinyl acetate copolymer, vinylpyrrolidone and dimethylaminoethyl / methacrylic acid copolymer, quaternized vinylpyrrolidone / dimethylaminoethyl / methacrylic acid copolymer, vinylpyrrolidone and Modified products of polyvinylpyrrolidone such as methacrylamidopropyl trimethylammonium chloride copolymer; carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, etc. Loose; Modified products of cellulose such as cationized hydroxyethyl cellulose; Synthetic resins such as polyester, polyacrylic acid (ester), melamine resin, or modified products thereof, polyester and polyurethane copolymer; poly (meth) acrylic acid, Examples include poly (meth) acrylamide, oxidized starch, phosphate esterified starch, self-modified starch, cationized starch, or various modified starches, polyethylene oxide, sodium polyacrylate, and sodium alginate. These may be used individually by 1 type and may use 2 or more types together.
Among these, from the viewpoint of ink absorbability, polyvinyl alcohol, cation-modified polyvinyl alcohol, acetal-modified polyvinyl alcohol, polyester, polyurethane, a copolymer of polyester and polyurethane, and the like are preferable.

The water-dispersible polymer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, polyvinyl acetate, ethylene-vinyl acetate copolymer, polystyrene, styrene- (meth) acrylate ester copolymer Polymer, (meth) acrylic acid ester polymer, vinyl acetate- (meth) acrylic acid (ester) copolymer, styrene-butadiene copolymer, ethylene-propylene copolymer, polyvinyl ether, silicone-acrylic copolymer Coalescence, etc.
The water dispersible polymer may contain a crosslinking agent or may be a copolymer having self-crosslinking properties.
Examples of the crosslinking agent include methylolated melamine, methylolated urea, methylolated hydroxypropylene urea, isocyanate, and the like.
Examples of the copolymer having self-crosslinking property include copolymers containing units such as N-methylolacrylamide.

  As content of the said aqueous polymer, 2-100 mass parts is preferable with respect to 100 mass parts of said pigments, and 3-50 mass parts is more preferable. The amount of the aqueous polymer added is determined so that the transfer amount of pure water in the recording medium falls within a desired range.

When the dye contained in the ink composition is water-dispersible, a cationic organic compound can be added to the coating layer depending on the purpose.
Examples of the cationic organic compound include primary to tertiary amines that react with a sulfonic acid group, a carboxyl group, an amino group, or the like in a direct dye or acidic dye in water-soluble ink to form an insoluble salt. Examples include monomers, oligomers and polymers of quaternary ammonium salts. Among these, an oligomer or polymer of primary to tertiary amine or quaternary ammonium salt is preferable.

Examples of the cationic organic compound include dimethylamine / epichlorohydrin polycondensate, dimethylamine / ammonia / epichlorohydrin condensate, poly (trimethylaminoethyl methacrylate / methyl sulfate), diallylamine hydrochloride / acrylamide copolymer, (Diallylamine hydrochloride / sulfur dioxide), polyallylamine hydrochloride, poly (allylamine hydrochloride / diallylamine hydrochloride), acrylamide / diallylamine copolymer, polyvinylamine copolymer, dicyandiamide, dicyandiamide / ammonium chloride / urea / formaldehyde condensate , Polyalkylene polyamine dicyandiamide ammonium salt condensate, dimethyl diallyl ammonium chloride, polydiallyl methylamine hydrochloride, poly (diallyl dimethyl ester) Ruammonium chloride), poly (diallyldimethylammonium chloride / sulfur dioxide), poly (diallyldimethylammonium chloride / diallylamine hydrochloride derivative), acrylamide / diallyldimethylammonium chloride copolymer, acrylate / acrylamide / diallylamine hydrochloride copolymer Products, ethyleneimine derivatives such as polyethyleneimine and acrylicamine polymer, and polyethyleneimine alkylene oxide modified products. These may be used individually by 1 type and may use 2 or more types together.
Among these, it is preferable to use a combination of a low molecular weight cationic organic compound and another relatively high molecular weight cationic organic compound. By combining the low molecular weight cationic organic compound with other relatively high molecular weight cationic organic compounds, the image density may be improved and feathering may be further reduced as compared to the case of using alone.
As the low molecular weight cationic organic compound, for example, dimethylamine / epichlorohydrin polycondensate, polyallylamine hydrochloride and the like are preferable.
As the high molecular weight cationic organic compound, for example, poly (diallyldimethylammonium chloride) is preferable.

The cation equivalent of the cationic organic compound by colloid titration method (using polyvinyl potassium sulfate and toluidine blue) is preferably, for example, 3 to 8 meq / g. When the cation equivalent is within this range, a good effect can be obtained within the range of the dry adhesion amount described later.
Here, for the measurement of the cation equivalent by the colloid titration method, the cationic organic compound is diluted with distilled water so as to have a solid content of 0.1% by mass, and the pH is not adjusted.

The dry adhesion amount of the cationic organic compound is preferably, for example, 0.3 to 2.0 g / m ² . When the dry adhesion amount of the cationic organic compound is lower than 0.3 g / m ² , sufficient image density improvement and feathering reduction effects may not be obtained.

-Surfactant-
When the surfactant is added to the coating layer, the water resistance of the image is improved, the image density is increased, and bleeding is improved.
There is no restriction | limiting in particular as said surfactant, Although it can select suitably according to the objective, Anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant are mentioned. Of these, nonionic active agents are particularly preferred.

Examples of the nonionic activator include higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, higher aliphatic amine ethylene oxide adducts, and fatty acid amides. Ethylene oxide adduct, fat ethylene oxide adduct, polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl ether of polyhydric alcohol, And fatty acid amides of alkanolamines. These may be used individually by 1 type and may use 2 or more types together.
The polyhydric alcohol is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include glycerol, trimethylolpropane, pentaerythritol, sorbitol, and sucrose.
As the ethylene oxide adduct, one obtained by substituting a part of ethylene oxide with an alkylene oxide such as propylene oxide or butylene oxide is also effective as long as water solubility can be maintained.
The substitution rate of the alkylene oxide in the ethylene oxide adduct is preferably 50% or less.
The HLB (hydrophilic / lipophilic ratio) of the nonionic active agent is preferably 4 to 15, and more preferably 7 to 13.

  As content of the said surfactant, 0-10 mass parts is preferable with respect to 100 mass parts of said cationic organic compounds, and 0.1-1.0 mass part is more preferable.

  Other components can be added to the coating layer as needed, as long as the object and effect of the present invention are not impaired. Examples of the other components include additives such as alumina powder, pH adjuster, preservative, and antioxidant.

There is no restriction | limiting in particular as a formation method of the said coating layer, According to the objective, it can select suitably, It can carry out by the method of impregnating or apply | coating a coating layer liquid on the said support body.
The impregnation or coating method of the coating layer liquid is not particularly limited and may be appropriately selected depending on the intended purpose. For example, conventional size press, gate roll size press, film transfer size press, blade coater, rod coater Coating with various coating machines such as air knife coater, curtain coater, etc., impregnating or adhering with conventional size press, gate roll size press, film transfer size press etc. installed in paper machine and finishing on machine , Etc. Among these, the on-machine finishing method is excellent in terms of cost.
There is no restriction | limiting in particular in the adhesion amount of the said coating layer liquid, According to the objective, it can select suitably, 0.5-20 g / m < ² > is preferable at solid content, and 1-15 g / m < ² > is more preferable. .
In addition, you may dry as needed after the said impregnation or application | coating.
There is no restriction | limiting in particular as temperature of the said drying, Although it can select suitably according to the objective, About 100-250 degreeC is preferable.

  The recording medium may further include a back layer on the back surface of the support, another layer between the support and the coating layer, or another layer between the support and the back layer, and a protective layer on the coating layer. Can also be provided. Each of these layers may be a single layer or a plurality of layers.

(ink cartridge)
The ink cartridge of the present invention contains the ink composition in the ink media set of the present invention in a container, and further includes other members appropriately selected as necessary.
The container is not particularly limited, and its shape, structure, size, material and the like can be appropriately selected according to the purpose. Preferred examples include those possessed.

(Inkjet recording apparatus and inkjet recording method)
The ink jet recording apparatus of the present invention includes at least ink flying means, and further includes other means appropriately selected as necessary, for example, stimulus generation means and control means.
The ink jet recording method of the present invention includes at least an ink flying process, and further includes other processes appropriately selected as necessary, for example, a stimulus generation process, a control process, and the like.
The ink jet recording method of the present invention can be preferably carried out by the ink jet recording apparatus of the present invention, and the ink flying step can be suitably carried out by the ink flying means. Moreover, the said other process can be suitably performed by the said other means.

-Ink flying process and ink flying means-
The ink flying step is a step of forming an image by applying a stimulus to the ink composition in the ink media set of the present invention and causing the ink composition to fly.
The ink flying means is means for forming an image by applying a stimulus to the ink composition in the ink media set of the present invention and causing the ink composition to fly. The ink flying means is not particularly limited, and examples thereof include various nozzles for ejecting ink.
In the present invention, it is preferable that at least a part of the liquid chamber portion, the fluid resistance portion, the vibration plate, and the nozzle member of the ink jet head is formed of a material containing at least one of silicon and nickel.
The nozzle diameter of the inkjet nozzle is preferably 30 μm or less, and preferably 1 to 20 μm.

The stimulus can be generated by the stimulus generating means, for example.
There is no restriction | limiting in particular as said irritation | stimulation, According to the objective, it can select suitably, For example, a heat | fever, a pressure, a vibration, light, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, heat and pressure are preferable.

Examples of the stimulus generating means include a heating device, a pressurizing device, a piezoelectric element, a vibration generating device, an ultrasonic oscillator, a light, and the like.
Specific examples of the stimulus generating means include, for example, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by film boiling of a liquid using an electrothermal transducer such as a heating resistor, and a metal phase change caused by a temperature change. Shape memory alloy actuators using electrostatic force, electrostatic actuators using electrostatic force, and the like.

  There is no particular limitation on the mode of flying of the ink composition, and it varies depending on the type of the stimulus. For example, when the stimulus is “heat”, a recording signal is output to the ink composition in the recording head. For example, a thermal head is used to generate bubbles in the ink composition by the thermal energy, and the pressure of the bubbles causes the ink composition to drop from the nozzle holes of the recording head. And a method of discharging and jetting. Further, when the stimulus is “pressure”, for example, by applying a voltage to a piezoelectric element bonded to a position called a pressure chamber in an ink flow path in the recording head, the piezoelectric element bends and the volume of the pressure chamber is increased. The ink composition is ejected and ejected as droplets from the nozzle holes of the recording head.

  The size of the droplet of the ink composition to be ejected is preferably 3 to 40 pl, the speed of ejection and ejection is preferably 5 to 20 m / s, and the driving frequency is 1 kHz or more. The resolution is preferably 300 dpi or more.

  The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as sequencers and computers.

  Here, the ink cartridge, the ink jet recording method, and the ink jet recording apparatus of the present invention will be described with reference to the accompanying drawings. However, the following is only one embodiment and does not limit the present invention. .

Here, FIG. 1 is a schematic front view of a mechanism portion of a serial type ink jet recording apparatus equipped with an ink cartridge having a recording liquid storage portion storing the ink composition of the present invention.
The mechanism of this ink jet recording apparatus has a main support guide rod 3 and a sub support guide rod 4 mounted between the side plates 1 and 2 on both sides in a substantially horizontal positional relationship, and the main support guide rod 3 and the sub support guide. The carriage 4 is supported by the rod 4 so as to be slidable in the main scanning direction. The carriage unit 5 has four heads 6 for discharging yellow (Y) ink, magenta (M) ink, cyan (C) ink, and black (Bk) ink, respectively, and an ejection surface (nozzle surface) 6a. Mount downward. In addition, on the upper side of the head 6 of the carriage unit 5, four ink cartridges 7y, 7m, 7c, and 7k, which are ink supply bodies for the respective colors for supplying ink to the four heads 6, are replaceably mounted. ing.

The carriage unit 5 is connected to a timing belt 11 stretched between a drive pulley (drive timing pulley) 9 and a driven pulley (idler pulley) 10 that are rotated by the main scan motor 8, and the main scan motor 8 is connected to the carriage unit 5. By controlling the driving, the carriage 5, that is, the four heads 6 are moved in the main scanning direction.
Further, sub frames 13 and 14 are erected on the bottom plate 12 connecting the side plates 1 and 2, and a conveying roller 15 for feeding the paper 16 in the sub scanning direction perpendicular to the main scanning direction is provided between the sub frames 13 and 14. Holds freely. A sub-scanning motor 17 is disposed on the side of the sub-frame 14, and a gear 18 and a conveying roller 15 fixed to the rotation shaft of the sub-scanning motor 17 are transmitted to transmit the rotation of the sub-scanning motor 17 to the conveying roller 15. And a gear 19 fixed to the shaft.
Between the side plate 1 and the subframe 12, a reliability maintenance / recovery mechanism (hereinafter also referred to as "subsystem") 21 of the head 6 is disposed. The sub-system 21 holds four cap means 22 for capping the ejection surface of each head 6 by a holder 23, and this holder 23 is held by a link member 24 so as to be swingable so that the carriage unit 5 can move in the main scanning direction. When the carriage unit 5 comes into contact with the engaging portion 25 provided on the holder 23 by the movement of the holder 23, the holder 23 is lifted up according to the movement of the carriage unit 5 and the ejection surface 6a of the inkjet head 6 is capped by the cap means 22, As the carriage unit 5 moves to the printing region side, the holder 23 is lifted down as the carriage unit 5 moves, so that the cap means 22 moves away from the ejection surface 6 a of the inkjet head 6.
The cap means 22 is connected to the suction pump 27 via the suction tube 26, forms an atmosphere opening port, and communicates with the atmosphere via the atmosphere opening tube and the atmosphere opening valve. The suction pump 27 discharges the sucked waste liquid to a waste liquid storage tank (not shown) through a drain tube or the like.
At the side of the holder 23, a wiper blade 28, which is a wiping means made of an elastic member such as a fiber member, a foam member, or rubber, for wiping the ejection surface 6a of the inkjet head 6 is attached to the blade arm 29. It is pivotally supported so that it can be swung by rotation of a cam that is rotated by a driving means (not shown).

Next, the ink cartridge 7 will be described with reference to FIGS. Here, FIG. 2 is an external perspective view of the ink cartridge before being loaded into the recording apparatus, and FIG. 3 is a front sectional view of the ink cartridge.
As shown in FIG. 3, the ink cartridge 7 includes an ink absorber 42 that absorbs ink of a required color in a cartridge main body 41. The cartridge body 41 is formed by adhering or welding an upper lid member 44 to an upper opening of a case 43 having a wide opening at the upper portion, and is made of, for example, a resin molded product. The ink absorber 42 is made of a porous material such as a urethane foam, and after being compressed and inserted into the cartridge body 41, the ink is absorbed.
An ink supply port 45 for supplying ink to the recording head 6 is formed at the bottom of the case 43 of the cartridge body 41, and a seal ring 46 is fitted on the inner peripheral surface of the ink supply port 45. The upper lid member 44 has an air opening 47 formed therein.
In the cartridge main body 41, the case 43 is compressed and deformed by the pressure applied to the wide side wall when the ink supply port 45 is closed and when the cartridge is handled during loading or transportation, or during vacuum packaging. In order to prevent internal ink from leaking, a cap member 50 is attached.
Further, as shown in FIG. 2, the air opening 47 is sealed by sticking a film-like sealing member 55 having an oxygen permeability of 100 ml / m ² or more to the upper lid member 44. The seal member 55 is sized to seal the plurality of grooves 48 formed around the air release port 47 as well as the atmosphere. In this way, by sealing the air opening 47 with the sealing member 55 having an oxygen permeability of 100 ml / m ² or more, the ink cartridge 7 is packaged under reduced pressure using a packaging member such as a non-permeable aluminum laminate film. Thus, even when the gas is dissolved in the ink due to the atmosphere in the space A (see FIG. 3) generated between the ink absorber 42 and the cartridge main body 41 when the ink is filled, the ink passes through the seal member 55. The air inside is discharged into a space between the packaging body outside the cartridge main body 41 having a high degree of vacuum, and the degree of deaeration of the ink is improved.

  FIG. 4 shows a configuration example of a recording cartridge that includes a recording liquid storage unit that stores an ink composition and a head unit that ejects ink droplets in the ink media set of the present invention. The recording unit 30 is of a serial type, and is mainly composed of an inkjet head 6, an ink tank 41 that contains an ink composition supplied to the inkjet head 6, and a lid member that seals the inside of the ink tank 41. The part is composed. A large number of nozzles 32 for discharging the ink composition are formed in the inkjet head 6. The ink composition is guided from the ink tank 41 to a common liquid chamber (not shown) via an ink supply pipe (not shown), and discharged from the nozzle 32 in response to an electrical signal from the recording apparatus main body input from the electrode 31. Is done. This type of recording unit has a structure suitable for a head of a type that can be manufactured at low cost, a head called a thermal method or a bubble method, which uses thermal energy as a driving power source.

  The ink composition in the ink media set of the present invention is improved in wettability to a thermal element in a recording method such as bubble or thermal method, so that ejection stability and frequency stability can be obtained even with a small addition amount, It is also highly suitable for safety.

Here, the serial type ink jet recording apparatus as described above has been described, but the ink composition of the present invention has the same or a fraction of the density as the target image resolution in an arbitrary arrangement such as staggered nozzles. It is also possible to apply the present invention to an ink jet recording apparatus having a so-called line head, which is integrated in a line and arranged in the width of the recording medium or more.
The ink jet recording apparatus may be an apparatus having a complex function in combination with a fax machine, a scanner, a telephone, or the like, as well as a PC or a digital camera output printer.

<Heating heater>
The ink jet recording apparatus of the present invention can be equipped with a heat fixing device in order to promote fixing of the ink composition. Such a heat fixing apparatus will be described by taking as an example a case where it is mounted on an ink jet recording apparatus having a configuration in which a plurality of line type ink jet heads are arranged.

  For example, as shown in FIG. 5, the heating type fixing device 76 is provided on the downstream side of the recording head 70 </ b> B in the conveyance path and corresponding to a relatively close position. Here, an embodiment including a halogen heater 84 and a reflection plate 82 that reflects heat rays from the halogen heater 84 is shown as the heating type fixing device 76. As in this embodiment, in the present invention, the printing surface side of the recording medium (paper Pa) is heated in a non-contact manner. That is, since the printing part is heated from the surface, volatile components in the ink such as water can be efficiently dried. Here, as the heating-type fixing device 76, a halogen heater 84 as a heating unit, a reflection plate 82 that reflects heat rays from the halogen heater 84, a heating unit shielding member 86 that partitions the halogen heater 84 and the conveyance path, An embodiment including a heat insulating device 78 as a heat insulating portion that cuts off heat transfer from the halogen heater 84 to the recording head 70B will be described below.

  In this embodiment, the halogen heater 84 is disposed adjacent to the recording head 70B in the vicinity of the most downstream side in the conveyance direction of the paper Pa in the recording unit 26. This is because it is necessary to heat and fix the halogen heater 84 immediately after the image recording is completed. The halogen heater 84 heats the recording surface in a non-contact manner. As a result, the recording surface is dried, the drying of the ink is promoted, and the fixing speed is greatly improved. Further, since it is non-contact, it can be avoided that the dot shape on the recording surface of the paper Pa is broken and can be dried without degrading the image quality. The heating operation of the halogen heater 84 is controlled at a predetermined timing according to the conveyance of the paper Pa and the recording operation of the recording unit 26 by a control unit described later. Alternatively, the rogen heater 84 is provided with a thermostat (not shown) for controlling the temperature of the halogen heater 84. According to the temperature set by the thermostat, the fixing temperature is appropriately controlled in accordance with conditions such as the paper quality of the recording member, the conveyance speed, and the image density. The heating unit for heating the surface (recording surface) to which the ink of the paper Pa is attached is not limited to the halogen heater 84, and may be a halogen lamp, a sheathed heater, a ceramic heater, a thermistor, or the like. Good.

Further, the heating portion shielding member 86 is made of a wire mesh or the like in consideration of the safety aspect when the paper Pa is jammed, and is disposed at a position covering the surface of the halogen heater 84 from the lower side. The reflection plate 82 having one end connected to the heat insulating device 80 is made of, for example, bright alloy aluminum or the like, and has a curved portion that covers the halogen heater 84 from above. The curved portion of the reflecting plate 82 is set so that the heat rays from the halogen heater 84 are reflected by the inner surface of the curved portion of the reflecting plate 82 and the heat rays reach the recording surface most efficiently. In addition to the reflection plate 82, for example, the light of the lamp light source may be condensed on the surface (recording surface) of the paper Pa where the ink is adhered by an optical system of a lens system. In addition, when a light / heat condensing optical system is formed by combining a reflecting plate and such a lens system optical system, it can be dried more efficiently.
As shown in FIG. 5, the heat insulating device 78 is connected between the recording head 70 </ b> B and the halogen heater 84 in the head block 72 and close to the recording head 70 </ b> B. The heat insulating device 78 is made of, for example, a plate-shaped member made of an aluminum alloy having a good heat dissipation property or a heat-resistant plastic material and a material having a good heat dissipation property such as an aluminum sheet bonded thereto. The heat insulating device 78 has a substantially rectangular cylindrical cross-sectional shape. That is, in the heat insulating device 78, an air layer 80 is formed in the inside thereof so as to extend along the ejection port arrangement direction of the recording head 70B. Moreover, the both ends of the up-down direction of the heat insulation apparatus 78 are respectively opened with respect to the exterior. Accordingly, heat transfer from the halogen heater 84 to the recording head 70B is cut off, and the temperature rise of the recording heads 70C to 70B due to high heat is prevented. Alternatively, the heat generated from the halogen heater 84 is conducted and radiated to the heat insulating device 78 via the reflector 82.

Next, FIG. 6 will be described. FIG. 6 shows the recording unit 26 of the multi-nozzle ink jet recording apparatus in which the plurality of ink discharge ports shown in FIG. 5 are elongated so as to cover the recording width of the recording medium. FIG. As is apparent from FIG. 6, in the present invention, the heating means including the heating type fixing device 76 is printed by the multi-nozzle type recording heads 70Y, 70B and the like that are elongated in the width direction of the recording medium Pa. It is preferable to cover a range larger than the printing width. In other words, if the area heated by the heating means is larger than the printing width, there is more heating capacity than when only the printing width is heated, so that the ink can be dried efficiently. Can be done. More preferably, as shown in FIG. 6, it is more effective to set the region heated by such a heating means to a range larger than the width of the recording medium Pa.
The heating-type fixing device 76 is provided at the rear stage of the recording head 70B (provided at the most downstream side of the recording medium Pa conveyance). A plurality of such heating means are prepared, and each recording head 70C is provided. , 70M, 70Y, 70B, and it is more effective to dry the ink at the same time as the printing with each color ink is completed. It is possible to solve the problem that the image quality is deteriorated due to the color. Furthermore, if the heating means is arranged upstream of the recording head 70C so that the recording medium Pa is heated in advance before printing by the recording head 70C starts, more effective ink drying can be performed.

Next, other features will be described with reference to FIG. FIG. 7 shows an example in which the back surface heating means 87 is provided so that the recording medium Pa can be heated from the back side of the surface to be printed. Also in this case, the back surface heating means 87 extends in the multi-nozzle row arrangement direction and covers a range larger than the printing width of the recording medium Pa so as to perform effective heating. Furthermore, more effective heating and drying can be realized by setting the heated area to be larger than the width of the recording medium Pa.
Also in this case, the heating means is preferably a lamp heater such as a halogen heater, a ceramic heater having a heating element fired on its surface, microwave irradiation, or the like, but is not limited thereto. A heating roller having a nichrome wire disposed therein or a cylindrical glass-shaped heating roller having a lamp light source disposed therein is also preferably used. Furthermore, a ceramic heater roller having a heating element on its surface is also used as an efficient heating means.
FIG. 8 shows a case where such a back surface heating means 87 is brought into contact with the conveyor belt 40 for more effective heating and drying. In this case, the recording medium Pa is heated via the conveying belt 40. However, instead of the conveying belt 40 as other conveying means, for example, as a conveying means of a drum structure (or roller), a drum ( If the recording medium Pa is directly heated using the roller itself as a heating drum (roller), more effective heating and drying can be achieved.

In this case as well, a heating roller with a nichrome wire inside, a cylindrical glass-like heating roller with a lamp light source inside, or a ceramic heater roller with a heating element fired on the surface, etc., is used for efficient heating. It is preferably used as a heating means that is also a means and also serves as a conveying means. Needless to say, such a roller heating means that also serves as a conveying means makes the heating area larger than the width of the recording medium Pa to provide a heating means with a margin.
FIG. 9 is a diagram for explaining still another feature. In this embodiment, the surface to be printed is contact-heated and dried by the heating roller 88. In this case, the surface of the heating roller 88 needs to be made of a material that does not wet the ink. In the present invention, it is preferable that a fluorine-based material such as ethylene tetrafluoride, silicone rubber, or the like is used as such an ink repellent material to constitute the surface of the heating roller.

In the present invention, since the surface to be printed is brought into direct contact with the heating roller 88 and heated and dried as described above, the ink can be dried very efficiently. In addition, since the surface of the heating roller is made of a material that does not wet the ink, it is possible to avoid breaking the undried ink dot shape. Therefore, the ink on the recording medium Pa can be dried and fixed more effectively without degrading the image quality.
In the case where such a surface to be printed is contact-heated and dried by the heating roller 88, the heating area extends in the direction of the multi-nozzle row arrangement and the recording medium Pa as in the above-mentioned various heating means. An effective heating can be realized by covering a range larger than the printing width of. Further, more effective heating and drying can be realized by setting the heated area to be larger than the width of the recording medium Pa.
Further, in the above embodiment, it has been described that heating and drying are performed after printing, but the above-described various heating means are arranged in the transport path of the recording medium Pa before printing, and the recording medium Pa is provided. A method of performing printing after having been heated in advance is also a good method for effective ink drying.

(Ink record)
The ink recorded matter of the present invention is an ink recorded matter recorded by the ink jet recording apparatus and the ink jet recording method of the present invention.
The ink recorded matter of the present invention has an image formed using the ink composition in the ink media set on the recording medium in the ink media set of the present invention.
There is no restriction | limiting in particular as said recording medium, According to the objective, it can select suitably, The thing similar to the said recording medium is mentioned. These may be used individually by 1 type and may use 2 or more types together.

In the ink recorded matter of the present invention, the ink composition contains fine polymer particles including dyes and inorganic pigment particles, a water-soluble solvent, and water, and has a surface tension at 25 ° C. of 20 to 35 mN / m. The recording medium comprises a support and a coating layer on at least one surface of the support, and the recording of pure water at a contact time of 100 ms measured with a dynamic scanning absorptiometer. The transfer amount to the recording medium is 2 ml / m ² or more and less than 35 ml / m ² , and the transfer amount of pure water to the recording medium at a contact time of 400 ms is 3 ml / m ² or more and less than 40 ml / m ^2. Therefore, a high-quality image with high chroma and good color tone can be obtained even on a recording medium with low ink absorbability. Further, in the color printed matter, there is an effect of increasing the brightness (lightness) and vividness (saturation) of the color.
The ink recorded matter of the present invention can be suitably used for various purposes as materials on which various prints or images are recorded.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Preparation of polymer>
The following three types of polymers were prepared.
-Polymer 1
-Styrene-acrylic polymer (product name: Jonkrill 586, manufactured by Johnson Polymer Co., Ltd., mass average molecular weight = 4,600, glass transition temperature (Tg) = 60 ° C.)

-Polymer 2-
In a four-necked flask with a capacity of 2 liters equipped with a dehydration tube, thermometer, nitrogen gas introduction tube, and stirring device, put the ingredients of the following formulation, and raise the temperature to 180 ° C over 3 hours while dehydrating. A condensation reaction was performed to synthesize a polyester resin.
<Prescription>
・ Cardura E-10P (Substance name: Decanoic acid epoxy ester, manufactured by Japan Epoxy Resin Co., Ltd.) 10 parts by mass Adipic acid 27 parts by mass Hexahydrophthalic anhydride 42 parts by mass Neopentyl Glycol: 2 parts by mass Trimethylolpropane: 26 parts by mass Dibutyltin dioxide: 0.1 parts by mass

-Polymer 3-
In a four-necked flask equipped with a thermometer, a nitrogen gas inlet tube, a stirrer, and a reflux condenser, the raw materials having the following formulation were put and reacted at 80 ° C. for 3 hours, and then 0.01 parts by weight of dibutyltin dilaurate And further reacted at the same temperature for 5 hours. After allowing the reaction mixture to cool, 1 part by mass of ethylenediamine was added and reacted for 1 hour to synthesize a polyurethane resin.
<Prescription>
・ Methyl ethyl ketone: 90 parts by mass ・ 2,2-dimethylolpropionic acid: 13 parts by mass ・ Polylactone diol: 52 parts by mass ・ Isophorone diisocyanate: 35 parts by mass

-Preparation of mill base-
<Millbase prescription (C-1)>
Solvent Blue 44 (cyan oil-soluble dye, Clariant Japan Co., Ltd., Savinyl Cyan GLS) 15 parts by mass Silica fine particles (Nippon Aerosil Co., Ltd., Aerosil-RX200) 5 parts by mass Polymer 1・ ・ 15 parts by mass ・ Ion-exchanged water ・ ・ ・ 65 parts by mass

  When 2-amino-2-methyl-1,3-propanediol is added to polymer 1 and dissolved in water, and the oil-soluble dye solvent blue 44 and silica fine particles are mixed and sufficiently wetted, a dyno mill KDL A is used as a kneading apparatus. A mold (manufactured by WAB) was filled with zirconia beads having a diameter of 0.5 mm and kneaded at 2,000 rpm for 40 minutes. Add 3 parts by mass of 1N hydrochloric acid to the resulting mill base and stir, then add 400 parts by mass of ion-exchanged water, stir well, separate into pigment paste and water using a centrifuge, and remove the supernatant. The operation was repeated several times. To this, 1.0 part by mass of 2-amino-2-methyl-1,3-propanediol as a basic compound was added, and kneading was again performed using a dyno mill KDL A type. The mill base (C-1) having a dye concentration of 15% by mass was produced by taking out the mill base and filtering it through a 1 μm filter.

<Millbase prescription (Y-2)>
Disperse Yellow 160 (Arimoto Chemical Co., Ltd., yellow disperse dye, Plast Yellow 8050) 15 parts by mass Alumina fine particles (Sumitomo Chemical Co., Ltd. APK-G008) 3 parts by mass Polymer 2 ... 15 parts by mass ・ Ion-exchanged water ... 67 parts by mass

  Using the above mill base formulation (Y-2), it was prepared in the same manner as mill base (C-1). The dye concentration of the mill base (Y-2) was 15% by mass.

<Millbase prescription (M-2)>
Solvent Red 218 (manufactured by Taoka Chemical Co., Ltd., magenta oil-soluble dye, Oleosol Fast Pink FB) ... 16 parts by mass Silica fine particles (Aerosil-RX200, manufactured by Nippon Aerosil Co., Ltd.) ... 8 parts by mass Polymer 2 ... 16 parts by mass ・ Ion-exchanged water ... 60 parts by mass

  Using the above mill base formulation (M-2), it was prepared in the same manner as mill base (C-1). The dye density | concentration of the mill base (M-2) was 15 mass%.

<Millbase prescription (M-3)>
Solvent Red 218 (Taoka Chemical Co., Ltd., magenta oil-soluble dye, Oleosol Fast Pink FB): 16 parts by mass Titanium dioxide fine particles (Ishihara Sangyo Co., Ltd., PT-401M): 4 parts by mass Polymer 3 ... 16 parts by mass ・ Ion-exchanged water ... 64 parts by mass

  Using the above mill base formulation (M-3), it was prepared in the same manner as mill base (C-1). The dye density | concentration of the mill base (M-3) was 15 mass%.

  In the preparation of the mill base, the volume average particle diameter of polymer fine particles including the prepared dye and inorganic pigment particles was measured. The results are shown in Table 1. The measurement was performed using UPA150 manufactured by Microtrack.

<Preparation of ink composition 1>
-Formulation of ink composition 1-
Millbase (C-1): 40 parts by mass Glycerin: 6 parts by mass 1,3-butanediol: 18 parts by mass Surfactant represented by the following formula (10) 2 parts by mass C ₁₃ H ₂₇ —O— (CH ₂ CH ₂ O) ₃ —CH ₂ COONa Formula (10)
・ 3-Methyl-2,4-heptanediol: 2 parts by mass ・ Proxel LV (manufactured by Avecia, antiseptic / antifungal agent): 0.1 part by mass ・ Ion exchange water: 31.9 parts by mass

  A vehicle is prepared by dissolving glycerin, 1,3-butanediol, 3-methyl-2,4-heptanediol, a surfactant represented by the above formula (10) and proxel LV in ion-exchanged water, and mill base ( After mixing with C-1), the mixture was filtered with a filter having an average pore diameter of 1 μm to prepare cyan ink for ink jet recording (ink composition 1).

<Preparation of ink composition 2>
-Formulation of ink composition 2-
Millbase (M-2): 50 parts by mass Glycerin: 9 parts by mass N-methyl-2-pyrrolidone: 18 parts by mass FT-110 (manufactured by Neos, fluorinated surfactant ) ... 1 part by mass-3-methyl-2,4-heptanediol ... 2 parts by mass-Proxel LV (manufactured by Avecia, antiseptic / antifungal agent) ... 0.1 part by mass ..19.9 parts by mass

  A magenta ink for ink-jet recording (ink composition 2) was produced in the same manner as the preparation method of the ink composition 1 using the ink formulation.

<Preparation of ink composition 3>
-Formulation of ink composition 3-
Millbase (Y-2): 50 parts by mass Glycerin: 9 parts by mass 1,3-butanediol: 18 parts by mass Surfactant represented by the following formula (11): 2 parts by mass C ₁₃ H ₂₇ —O— (CH ₂ CH ₂ O) ₈ —H Formula (11)
-2,2,4-trimethyl-1,3-pentanediol-2 parts by mass-Proxel LV (manufactured by Abecia, antiseptic / antifungal agent)-0.1 parts by mass-Ion exchange water-18 .9 parts by mass

  A yellow ink for ink jet recording (ink composition 3) was prepared in the same manner as the preparation method of the ink composition 1 using the ink formulation.

<Preparation of ink composition 4>
-Formulation of ink composition 4-
Mill base (M-3): 50 parts by mass Glycerin: 9 parts by mass 1,3-butanediol: 18 parts by mass Surfactant represented by the following formula (11): 2 parts by mass C ₁₃ H ₂₇ —O— (CH ₂ CH ₂ O) ₈ —H Formula (11)
-2,2,4-trimethyl-1,3-pentanediol-2 parts by mass-Proxel LV (manufactured by Abecia, antiseptic / antifungal agent)-0.1 parts by mass-Ion exchange water-18 .9 parts by mass

  A magenta ink for ink-jet recording (ink composition 4) was produced in the same manner as the preparation method of the ink composition 1 using the ink formulation.

<Preparation of ink composition 5>
-Formulation of ink composition 5-
Millbase (C-1): 50 parts by mass Glycerin: 9 parts by mass 3-Methyl-1,3-butanediol: 18 parts by mass FT-110 (Neos Corporation, fluorine system Surfactant) ... 1 part by mass-3-methyl-2,4-heptanediol ... 2 parts by mass-Proxel LV (Abesia, antiseptic / antifungal agent) ... 0.1 part by mass-Ion Exchanged water ... 19.9 parts by mass

  A cyan ink for ink jet recording (ink composition 5) was prepared in the same manner as the preparation method of the ink composition 1 using the ink formulation.

<Preparation of ink composition 6>
-Formulation of ink composition 6-
Millbase (C-1) 50 parts by mass Glycerin 9 parts by mass 1,6-hexanediol 18 parts by mass Proxel LV (Avecia, antiseptic / antifungal agent) 0.1 parts by mass ・ Ion-exchanged water: 22.9 parts by mass

  A cyan ink for ink jet recording (ink composition 6) was prepared in the same manner as the method for preparing ink composition 1 using the ink formulation.

<Preparation of ink composition 7>
-Formulation of ink composition 7-
Direct Blue 199 (Ciba Specialty Chemicals, cyan dye, Irgasperse Jet Cyan RL) 9 parts by mass Glycerin 9 parts by mass 3-methyl-1,3-butanediol 18 parts by mass FT-110 (manufactured by Neos Co., Ltd., fluorosurfactant) 1 part by mass 3-methyl-2,4-heptanediol ... 2 parts by mass Proxel LV (Abesia, antiseptic / antifungal agent) ) ... 0.1 parts by mass ・ Ion-exchanged water ... 60.9 parts by mass

  Direct dye Direct Blue 199, glycerin, 3-methyl-1,3-butanediol, 3-methyl-2,4-heptanediol, FT-110, and proxel LV are dissolved in ion-exchanged water, and the average pore size is 0.5 μm. The cyan ink for ink-jet recording (ink composition 7) was prepared.

-Mill base formulation (M-4)-
Solvent Red 218 (Taoka Chemical Co., Ltd., magenta oil-soluble dye, Oleosol Fast Pink FB) ... 14 parts by mass Dispersant represented by the following formula (12): 4 parts by mass
・ Ion exchange water: 82 parts by mass

  When the dispersing agent is dissolved in ion-exchanged water and the oil-soluble dye is mixed and sufficiently wetted, a dyno mill KDL A type (manufactured by WAB) is filled as a kneading device with zirconia beads having a diameter of 0.5 mm, Kneading was performed at 000 rpm for 2 hours to prepare a mill base (M-4).

<Preparation of ink composition 8>
-Formulation of ink composition 8-
Millbase (M-4): 50 parts by mass Glycerin: 9 parts by mass 1,3-butanediol: 18 parts by mass Surfactant represented by the following formula (11) 2 parts by mass C ₁₃ H ₂₇ —O— (CH ₂ CH ₂ O) ₈ —H Formula (11)
-2,2,4-trimethyl-1,3-pentanediol-2 parts by mass-Proxel LV (manufactured by Abecia, antiseptic / antifungal agent)-0.1 parts by mass-Ion exchange water-18 .9 parts by mass

  A magenta ink for ink jet recording (ink composition 8) was produced in the same manner as the preparation method of the ink composition 1 using the ink formulation.

-Mill base formulation (M-5)-
Pigment Violet 19 (manufactured by Ciba Specialty Chemicals, magenta pigment, CROMOPHTAL Red 2020): 14 parts by mass Dispersant represented by the following formula (12): 4 parts by mass
・ Ion exchange water: 82 parts by mass

  Millbase (M-5) was prepared in the same manner as millbase (C-1) using the above millbase formulation.

<Preparation of ink composition 9>
-Formulation of ink composition 9-
Millbase (M-5): 50 parts by mass Glycerin: 9 parts by mass 1,3-butanediol: 18 parts by mass Surfactant represented by the following formula (11) 2 parts by mass C ₁₃ H ₂₇ —O— (CH ₂ CH ₂ O) ₈ —H Formula (11)
-2,2,4-trimethyl-1,3-pentanediol-2 parts by mass-Proxel LV (manufactured by Abecia, antiseptic / antifungal agent)-0.1 parts by mass-Ion exchange water-18 .9 parts by mass

  A magenta ink for ink-jet recording (ink composition 9) was produced in the same manner as the method for preparing ink composition 1 using the above ink formulation.

<Preparation of ink composition 10>
-Formulation of ink composition 10-
As described below, the glycerin of the ink composition 4 is increased from 9 parts by mass to 13 parts by mass, 1,3-butanediol is increased from 18 parts by mass to 26 parts by mass, and from 18.9 parts by mass of ion-exchanged water to 6. A magenta ink for ink-jet recording (ink composition 10) was produced in the same manner as the preparation method of the ink composition 4 except that the amount was reduced to 9 parts by mass.
Mill base (M-3): 50 parts by mass Glycerin: 13 parts by mass 1,3-butanediol: 26 parts by mass Surfactant represented by the following formula (11): 2 parts by mass C ₁₃ H ₂₇ —O— (CH ₂ CH ₂ O) ₈ —H Formula (11)
-2,2,4-trimethyl-1,3-pentanediol-2 parts by mass-Proxel LV (manufactured by Abecia, antiseptic / antifungal agent)-0.1 parts by mass-Ion exchange water-6 .9 parts by mass

<Preparation of ink composition 11>
-Formulation of ink composition 11-
<Millbase prescription (M-6)>
・ Solvent Red 218 (Taoka Chemical Co., Ltd., magenta oil-soluble dye, Oleosol Fast Pink FB) ・ ・ ・ 16 parts by mass ・ Titanium dioxide fine particles (Ishihara Sangyo Co., Ltd., PT-401M) ... 4 parts by mass 3 ... 16 parts by mass · Ion-exchanged water ... 64 parts by mass The same as mill base (C-1) except that the mill base formulation (M-6) was used and the processing time of the kneading apparatus was changed to 20 minutes. It was prepared by the method. The dye concentration of the mill base (M-6) was 15% by mass.
In the preparation of the mill base, the volume average particle diameter of polymer fine particles including the prepared dye and inorganic pigment particles was measured. The results are shown in Table 1. The measurement was performed using UPA150 manufactured by Microtrack.

  Next, a magenta ink for ink jet recording (ink composition 11) was produced in the same manner as the preparation method of the ink composition 4 except that the mill base of the ink composition 4 was changed to (M-6).

<Preparation of ink composition 12>
-Formulation of ink composition 12-
Ink composition 12 was prepared in the same manner as ink composition 5 except that 3-methyl-1,3-butanediol was changed to 1,6-hexanediol in ink composition 5.

  Next, the viscosity and surface tension of the prepared ink compositions 1 to 12 were measured as follows. The results are shown in Table 2.

<Viscosity>
Measurement was performed at 25 ° C. using RC-500 manufactured by Toki Sangyo Co., Ltd.

<Surface tension>
Measurement was performed at 25 ° C. using a CBVP-Z type manufactured by Kyowa Interface Science Co., Ltd.

  Next, the pure water transfer amount of the following four types of recording media used for evaluation was measured. The results are shown in Table 3. The measurement was performed using a dynamic scanning absorption meter (K350 series D type, manufactured by Kyowa Seiko Co., Ltd.).

<Recording media>
Recording medium A: Aurora coat, basis weight = 104.7 g / m ² (manufactured by Nippon Paper Industries Co., Ltd.)
Recording medium B: POD gloss coat 100 g / m ² paper (Oji Paper Co., Ltd.)
・ Recording media C: Superfine paper (Seiko Epson Corporation)
Recording media D: Lumirror U10 (manufactured by TORAY Co., Ltd.)
-Recording medium E: TJ85FC Ink-jet mat coated paper (manufactured by Nippon Paper Industries Co., Ltd.)

(Examples 1-5 and Comparative Examples 1-13)
In Examples 1 to 5 and Comparative Examples 1 to 13, according to Tables 4 and 5, using the ink compositions 1 to 9 and the recording media A to E, an ink jet recording apparatus (Ipsio G7570, manufactured by Ricoh Co., Ltd.) ) Was used to prepare an ink recorded matter.
Next, image quality was evaluated in accordance with a beading (density unevenness) evaluation method, a spur stain evaluation method, and a saturation evaluation method as follows. The results are shown in Tables 4 and 5.

<Beading (density unevenness)>
The degree of beading of the green solid image portion of each image print was visually observed and evaluated according to the following criteria. Note that the beading rank sample is shown in FIG. 10 (in the figure, it is displayed in black and white but is actually green).
〔Evaluation criteria〕
Rank 4: There is no occurrence of beading and uniform printing.
Rank 3: Slight beading is observed.
Rank 2: The occurrence of beading is clearly recognized.
Rank 1: Significant beading is observed.

<Spur dirt>
The degree of offset contamination due to spurs from the solid portion to the background portion was visually evaluated. The rank evaluation was performed according to the following criteria. The acceptable level is 3 or higher.
Rank 3: No offset contamination at all.
Rank 2: Offset dirt appears faint.
Rank 1: Offset dirt is clearly visible.

<Saturation>
It was measured with a reflection type color spectrophotometric densitometer (manufactured by X-Rite). Calculate the ratio between the measured saturation value and the saturation value of the standard color (Japan color ver. 2) (yellow: 91.34, magenta: 74.55, cyan: 62.82) Table 4 shows the results of evaluation according to the evaluation criteria. The acceptable level is ◯ or higher.
-Evaluation criteria-
A: The ratio is 1.0 or more.
A: The ratio is 0.8 or more and less than 1.0.
Δ: Ratio is 0.7 or more and less than 0.8.
X: The ratio is less than 0.7.

(Examples 6-8 and Comparative Examples 14-16)
In Examples 6 to 8 and Comparative Examples 14 to 16, according to Tables 6 and 7, the ink compositions 10 to 12 and the recording media A to E were used, and an inkjet recording apparatus (Ipsio G7570, Ricoh Co., Ltd.). Ink records were prepared using
Next, in the same manner as in Examples 1 to 5 and Comparative Examples 1 to 13, image quality was evaluated according to a beading (density unevenness) evaluation method, a spur stain evaluation method, and a saturation evaluation method. The results are shown in Tables 6 and 7.

The ink media set of the present invention can provide a high-definition and high-quality image by combining a recording medium having a predetermined liquid absorption property and an ink composition having a predetermined surface tension. It can be suitably used for a recorded material, an ink jet recording apparatus, and an ink jet recording method.
The ink jet recording apparatus and the ink jet recording method of the present invention can be applied to various types of recording by the ink jet recording method, and are particularly suitable for, for example, an ink jet recording printer, a facsimile apparatus, a copying apparatus, and a printer / fax / copier multifunction machine. Can be applied to.

FIG. 1 is a schematic front view showing a configuration example of a serial type ink jet recording apparatus equipped with an ink cartridge containing an ink composition used in the present invention. FIG. 2 is an external perspective view showing an example of an ink cartridge before being loaded into the ink jet recording apparatus of the present invention. FIG. 3 is a front sectional view of the ink cartridge of FIG. FIG. 4 is an external perspective view showing an example of a recording unit integrated with the recording head. FIG. 5 is a schematic front view of the heat fixing device. FIG. 6 is a diagram for explaining the relationship between the heating means and the portion to be printed. FIG. 7 is a schematic front view of a heating type fixing device provided with a back surface heating means. FIG. 8 is a schematic front view of a heating type fixing device provided with a back surface heating means in contact with the conveyance belt. FIG. 9 is a schematic front view of the printing surface contact heating type fixing device. FIG. 10 is a rank sample representing the degree of beading.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Side plate 2 Side plate 3 Main support guide rod 4 Sub support guide rod 5 Carriage unit 6 Head 6a Discharge surface (nozzle surface)
7 Ink Cartridge 7y Ink Cartridge 7m Ink Cartridge 7c Ink Cartridge 7k Ink Cartridge 8 Main Scanning Motor 9 Drive Pulley (Drive Timing Pulley)
10 Driven pulley (idler pulley)
DESCRIPTION OF SYMBOLS 11 Timing belt 12 Bottom plate 13 Sub frame 14 Sub frame 15 Conveyance roller 16 Paper 17 Sub scanning motor 18 Gear 19 Gear 21 Sub system 22 Cap means 23 Holder 24 Link member 25 Engagement part 26 Suction tube 27 Suction pump 28 Wiper blade 29 Blade Arm 30 Recording unit 31 Electrode 32 Nozzle 33 Ink tank 41 Cartridge body 42 Ink absorber 43 Case 44 Upper lid member 45 Ink supply port 46 Seal ring 47 Air release port 50 Cap member 55 Seal member A Space 26 Recording unit 72 Head block 72Y Yellow Head block for ink 72M Head block for magenta ink 72C Head block for cyan ink 72B Head block for black ink 78 Thermal insulation Location 80 air layer 84 halogen heater,

Claims (14)

An ink media set having an ink composition and a recording medium,
The ink composition contains polymer fine particles including dyes and inorganic pigment particles, a water-soluble solvent, and water, and has a surface tension at 25 ° C. of 20 to 35 mN / m,
The recording medium comprises a support and a coating layer on at least one surface of the support, and pure water is applied to the recording medium at a contact time of 100 ms measured with a dynamic scanning absorptiometer. The transfer amount is 2 ml / m ² or more and less than 35 ml / m ² , and the transfer amount of pure water to the recording medium at a contact time of 400 ms is 3 ml / m ² or more and less than 40 ml / m ^2. Ink media set.   The ink media set according to claim 1, wherein the ink composition has a viscosity at 25 ° C. of 5 to 50 mPa · s.   The ink media set according to claim 1, wherein the dye is at least one of an oil-soluble dye and a disperse dye.   The ink media set according to any one of claims 1 to 3, wherein the inorganic pigment particles are any of titanium dioxide particles, alumina particles, and silica particles.   The ink according to any one of claims 1 to 4, wherein the polymer constituting the polymer fine particles including the dye and the inorganic pigment fine particles is at least one of a polyester resin, a polyurethane resin, a vinyl resin, and an acrylic resin. Media set.   The ink media set according to any one of claims 1 to 5, wherein the volume average particle diameter of polymer fine particles including dye and inorganic pigment fine particles is 5 to 200 nm.   Water-soluble solvents are glycerin, diethylene glycol, triethylene glycol, 1,3-butanediol, 1,6-hexanediol, propylene glycol, 1,5-pentanediol, dipropylene glycol, trimethylolpropane, and 3-methyl- The ink media set according to claim 1, which is at least one of 1,3-butanediol.   The ink media set according to any one of claims 1 to 7, comprising any one of a polyol compound having 8 or more carbon atoms and a glycol ether compound.   An ink cartridge comprising the ink composition of the ink media set according to claim 1 contained in a container.   An ink flying step of recording an image on a recording medium in the ink media set by applying a stimulus to the ink composition in the ink media set according to claim 1 and causing the ink composition to fly. An ink jet recording method comprising:   The inkjet recording method according to claim 10, wherein the stimulus is at least one selected from heat, pressure, vibration, and light.   An ink flying means for recording an image on a recording medium in the ink media set by applying a stimulus to the ink composition in the ink media set according to claim 1 and causing the ink composition to fly. An ink jet recording apparatus comprising:   The inkjet recording apparatus according to claim 12, wherein the stimulus is at least one selected from heat, pressure, vibration, and light.   An ink recorded matter comprising an image recorded using the ink composition in the ink media set on a recording medium in the ink media set according to any one of claims 1 to 8.